Barrier compositions and methods of using the same

Abstract

A barrier composition is provided comprising a water dispersion of one or more functional adjuvants, and one or more nanocellulose. A method for improving the retention, reactivity, and / or distribution of a functional adjuvant disposed on a substrate is also provided. The substrate has a substrate surface and includes a fiber having a fiber surface, wherein the barrier composition is applied to or disposed on the substrate.

Description

Technical Field

[0001] This disclosure generally relates to a composition comprising an aqueous dispersion of one or more functional additives formulated with nanocellulose. The functional additives may be sizing agents, barrier agents, and combinations thereof. The nanocellulose may be selected, for example, from microfibrillated cellulose (MFC), nanofibrillated cellulose (NFC), microcrystalline cellulose (MCC), nanocrystalline cellulose (NCC), and combinations thereof. The composition may be applied or disposed on the surface of a substrate to provide the substrate with improved retention, reactivity, or distribution of the functional additives, resulting in a coated article on the substrate exhibiting enhanced cellulose fiber reactivity, increased retention of functional additives, and / or improved barrier properties against oils, greases, gases, water, and water vapor. Background Technology

[0002] Dry cellulose fibers from dry molding processes lack interaction and reactivity with sizing agents (e.g., alkyl ketene dimers (AKD), alkenyl ketene dimers (AnKD), and alkenyl succinic anhydride (ASA)). Therefore, after the sizing agent is applied to the dry cellulose fibers, poor bonding of AKD, AnKD, or ASA to the fibers and uneven distribution of AKD, AnKD, or ASA are observed in dry-molded articles. This, in turn, reduces the performance of the sizing agent and other additives when used as functional barrier compositions. Furthermore, the high proportion of unbonded AKD, AnKD, or ASA in dry-molded articles makes the final product non-compliant with regulatory requirements, for example, when the article is intended for food contact applications.

[0003] To improve the retention of functional additives (such as sizing agents or barrier agents) on substrates, efforts were made to enhance the interaction and reactivity between compositions and substrates used in applications such as dry molding. It was quickly discovered that compositions containing nanocellulose could serve as carriers for sizing agents in dry molding processes.

[0004] In fact, it has been observed that by combining one or more nanocelluloses (e.g., microfibrillated cellulose (MFC), nanofibrillated cellulose (NFC), microcrystalline cellulose (MCC), nanocrystalline cellulose (NCC), and combinations thereof) with functional additives, the composition provides improved retention, reactivity, and / or distribution of the functional additives on the substrate.

[0005] Microfibrillated cellulose (MFC) and nanofibrillated cellulose (NFC) are obtained from cellulose pulp through mechanical milling and possess extremely high surface areas and unique interpenetrating network structures. Microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) are also refined wood pulps and can be synthesized by combining different processes, such as reactive extrusion, mechanical milling, ultrasonic treatment, steam explosion, and enzymatic and / or acid hydrolysis. These processes can be performed using cellulases (e.g., endo-1,4-D-glucanase, glucosidase, exo-1,4-D-glucanase) or by using inorganic acids (e.g., H₂SO₄, HCl, and HBr) and ionic liquids. These agents act to disrupt amorphous regions while preserving crystalline domains. Nanocellulose obtained during the pulping, processing, and finishing of fibers is typically characterized by high surface area, abundant reactive hydroxyl groups (-OH), and the presence of anionic surface charges (e.g., R-COO-, or RO-SO₃-). For the purposes of this application, the term "nanocellulose" means cellulose including microfibrillated cellulose (MFC) or cellulose microfibrils (CMF), nanofibrillated cellulose (NFC) or cellulose nanofibrils (CNF), microcrystalline cellulose (MCC) or cellulose microcrystals (CMC), nanocrystalline cellulose (NCC) or cellulose nanocrystals (CNC), and combinations thereof.

[0006] Although not bound by theory, it is believed that nanocellulose with abundant reactive hydroxyl groups (-OH) and anionic surface charges (e.g., R-COO-, or RO-SO3-) interacts and / or reacts with functional additives on its fiber surface, thereby providing a more uniform distribution and / or more covalently bonded functional additives to the fibers on the substrate during dry molding processes. It is also thought that the anionic surface charges interact with cationic sizing agents or barrier agents to improve the retention of functional additives on the substrate, while the reactive hydroxyl groups on the fiber surface ensure high reactivity with sizing agents and / or barrier agents, thus forming more covalent bonds between the fibers and functional additives.

[0007] Extensive research has shown that the presence of nanocellulose in aqueous dispersions containing one or more functional additives can significantly improve the retention, reactivity, and / or distribution of the functional additives.

[0008] This composition is useful in applications where an aqueous dispersion of one or more functional additives is used to impart barrier properties to substrates and articles, such as water resistance, water vapor resistance, oil and grease resistance, gas (e.g., oxygen) barrier properties, or other barrier properties, for applications such as dry molding or dry forming processes.

[0009] Therefore, one objective is to provide barrier compositions, coatings, and formulations with enhanced retention, reactivity, and / or distribution of functional additives on substrates, such as in dry molding applications, thereby providing better barrier performance than currently available.

[0010] Furthermore, other desirable features and characteristics of this disclosure will become apparent from the following detailed description, the appended claims, and the background art. Summary of the Invention

[0011] This overview section is provided in a simplified form to introduce the following concepts, which are further described in the detailed description below. This overview section is not intended to identify key or essential features of the claimed subject matter, nor is it intended to determine the scope of the claimed subject matter.

[0012] A barrier composition is provided that improves the retention, reactivity, or distribution of functional additives on a substrate surface. The composition comprises one or more nanocelluloses, such as microfibrillated cellulose (MFC), cellulose microfibrils (CMF), nanofibrillated cellulose (NFC), cellulose nanofibers (CNF), microcrystalline cellulose (MCC), cellulose microcrystals (CMC), nanocrystalline cellulose (NCC), cellulose nanocrystals (CNC), and combinations thereof; an aqueous dispersion of one or more functional additives; and water.

[0013] Also provided is a substrate composed of dry cellulose fibers and having improved barrier properties, the substrate comprising a substrate having a three-dimensional (3D) structure of cellulose fibers having a first surface and a second surface arranged opposite to each other, and a barrier layer disposed on the cellulose fibers in the three-dimensional structure and / or in direct contact with the outermost surface, the innermost surface, or both surfaces of the substrate.

[0014] The barrier layer includes a composition comprising an aqueous dispersion of one or more functional additives and one or more nanocelluloses, such as those selected from microfibrillated cellulose (MFC), cellulose microfibrils (CMF), nanofibrillated cellulose (NFC), cellulose nanofibrils (CNF), microcrystalline cellulose (MCC), cellulose microcrystals (CMC), nanocrystalline cellulose (NCC), cellulose nanocrystals (CNC), and combinations thereof.

[0015] Furthermore, a method for improving the retention, reactivity, or distribution of functional additives on a substrate is provided. The method includes providing a substrate with a three-dimensional (3D) structure having cellulose fibers having an outermost surface and an innermost surface arranged opposite to each other, and applying or otherwise disposing a barrier composition on the cellulose fibers in the three-dimensional structure of the substrate, and / or on the outermost surface, innermost surface, or both surfaces of the substrate. The barrier composition comprises an aqueous dispersion of one or more functional additives and one or more nanocellulose nanoparticles.

[0016] Finally, articles made by the compositions and methods described herein are provided. Detailed Implementation

[0017] The following detailed description is exemplary only and is not intended to limit the invention or its application and use. As used herein, the word "exemplary" means "as an example, instance, or illustration." Therefore, any "exemplary" embodiment described herein is not necessarily to be construed as preferred or advantageous relative to other embodiments. All embodiments described herein are exemplary embodiments intended to enable those skilled in the art to make or use the invention, and not to limit the scope of the invention as defined by the claims.

[0018] Furthermore, there is no intention to be bound by any express or implied theory set forth in the foregoing technical field, background art, invention content, or the following detailed description.

[0019] Unless otherwise specifically stated or obvious from the context, as used herein, the term “about” is understood to mean within the normal tolerance range in the field, such as within 2 standard deviations of the mean. “About” can be understood as within 10%, 5%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. “About” can also be understood to mean the exact value stated. Unless explicitly indicated from the context, all numerical values ​​provided herein are modified by the term “about”.

[0020] As used in this article, the term "paper" refers to paper products, including toilet paper, tissues, paper and paperboard, as well as molded fiber / pulp products.

[0021] A composition is provided comprising an aqueous dispersion of one or more functional additives, and one or more nanocelluloses.

[0022] In some aspects of the barrier composition, the one or more functional additives may be selected, for example, sizing agents, barrier agents, and combinations thereof.

[0023] In some aspects of the barrier composition, the one or more functional additives may be sizing agents selected from alkyl ketene dimers (AKD), alkenyl ketene dimers (AnKD), alkenyl succinic anhydride (ASA), rosin (e.g., free rosin, fortified rosin, and cationic rosin) and combinations thereof.

[0024] In some aspects of the barrier composition, the sizing agent may be present in the barrier composition in an amount of about 0.01 weight percent to about 50 weight percent, or in an amount of about 0.01 weight percent to about 15 weight percent.

[0025] In some other aspects of the barrier composition, the functional additive is a barrier agent selected from wax dispersions, latexes, solutions or dispersions of natural polymers, and combinations thereof.

[0026] In some aspects of the barrier composition, the barrier agent may be present in the barrier composition in an amount greater than 0% by weight to about 50% by weight, or in an amount of about 0.5% by weight to about 30% by weight.

[0027] In some aspects of the barrier composition, nanocellulose may be selected from microfibrillated cellulose (MFC), cellulose microfibrils (CMF), nanofibrillated cellulose (NFC), cellulose nanofibers (CNF), microcrystalline cellulose (MCC), cellulose microcrystals (CMC), nanocrystalline cellulose (NCC), cellulose nanocrystals (CNC), and combinations thereof.

[0028] In some aspects of the barrier composition, nanocellulose may be present in the barrier composition in an amount of about 5% to about 99.9% by weight, in an amount of about 10% to about 85% by weight, and in an amount of about 20% to about 70% by weight.

[0029] In some other aspects of the barrier composition, the one or more functional additives may be in a neutral, cationic or anionic emulsion system, and the sizing agent and the barrier agent have the same type of charge; preferably, the functional additives are in a neutral or cationic emulsion system.

[0030] In some other aspects of the barrier composition, the one or more nanocelluloses may be in a suspension, wherein the pH of the suspension is from about 6 to about 10, and may be from about 7.5 to about 8.5.

[0031] In some aspects of the barrier composition, nanocellulose has a concentration of at least about 5 m² / g (m²). 2The BET specific surface area is approximately 10 m² / g, and may have a minimum of about 10 m² / g. The BET specific surface area is calculated from the N₂ adsorption curve by the Brunauer-Emmet-Teller (BET) method according to ISO 9277:2010 standard, which applies to dried nanocellulose fibers prepared by supercritical CO₂ drying after solvent exchange.

[0032] In some other aspects of the barrier composition, the average fiber width of the nanocellulose is less than 1 micrometer, and can be less than 0.1 micrometer, as measured by electron microscopy.

[0033] In some aspects of the barrier composition, nanocellulose is present in a suspension or paste.

[0034] In some aspects of the barrier composition, nanocellulose and functional additives are present in a dry matter mass ratio greater than about 1:1 or greater than about 10:1 to 1:10.

[0035] In some other aspects of the barrier composition, the barrier agent may be selected from any barrier agent known in the industry, such as wax dispersions, wherein the wax is selected from paraffin wax, microcrystalline wax, polyethylene, polypropylene, Fischer-Tropsch wax, wood palm wax, palm wax, palm kernel wax, coconut wax, rapeseed wax, soybean wax, safflower wax, corn wax, sunflower wax, castor wax, carnauba wax, beeswax wax, shellac wax, candela wax, sugarcane wax, rice bran wax, stearates, laurates, oleates, ethylene-vinyl acetate copolymer (EVA), ethylene-propylene copolymer, and combinations thereof.

[0036] In some other aspects of the barrier composition, the barrier agent further comprises a thermoplastic polymer selected from hydrocarbon resins, polypropylene and propylene copolymers, polyethylene and ethylene copolymers, polystyrene and styrene copolymers, polyesters, styrene-maleic anhydride copolymers, derivatives, vinyl acetate-butyl acrylate copolymers, acrylate-methyl methacrylate copolymers, polyhydroxy fatty acid esters, polyhydroxybutyrate, styrene-butadiene copolymers, styrene-acrylic acid copolymers, butadiene-methyl methacrylate copolymers, polybutadiene, and combinations thereof.

[0037] In some other aspects of the barrier composition, the composition may further include additional additives, such as solutions or dispersions of natural polymers. Examples include starch, cellulose, lignin, hemicellulose, pectin, protein, rosin (e.g., free rosin, fortified rosin, cationic rosin, rosin esters, and rosin amides), polyterpenes, alginates, xanthan gum, soybean lecithin, lipids, disaccharides, monosaccharides, their derivatives (esterified, cationic, and carboxylated natural polymers), and combinations thereof.

[0038] A method for improving the retention, reactivity, or distribution of functional additives disposed on a substrate is also provided. The method includes the steps of: providing a substrate having a substrate surface and including fibers having a fiber surface; and disposing a barrier composition on the fiber surface and / or the surface of the substrate, and in direct contact with the fiber surface and / or the surface of the substrate, wherein the barrier composition comprises an aqueous dispersion containing one or more functional additives, and one or more nanocelluloses.

[0039] In some aspects of this method, the substrate may be a dry molding article and / or include raw materials and / or intermediate materials used in dry molding or dry forming processes.

[0040] In some aspects of the method, the one or more functional additives may be, for example, alkyl ketene dimers (AKD), alkenyl ketene dimers (AnKD), alkenyl succinic anhydride (ASA), rosin sizing agents (e.g., free rosin, fortified rosin, cationic rosin), wax dispersions, latexes, natural polymer solutions, polymer dispersions, and combinations thereof.

[0041] In some aspects of the method, the one or more functional additives constitute a greater than 0 weight percentage to about 50 weight percentage of the blocking composition, or 0.01 weight percentage to about 30 weight percentage, or about 0.5 weight percentage to about 15 weight percentage.

[0042] In some aspects of this method, nanocellulose may be selected from microfibrillated cellulose (MFC), cellulose microfibrils (CMF), nanofibrillated cellulose (NFC), cellulose nanofibers (CNF), microcrystalline cellulose (MCC), cellulose microcrystals (CMC), nanocrystalline cellulose (NCC), cellulose nanocrystals (CNC), and combinations thereof.

[0043] In some aspects of this method, the substrate can be selected from non-cellulose and cellulose fiber-based materials. For example, the substrate can be selected from mechanical pulp, chemimechanical pulp, chemical pulp, wood, non-wood plants, such as bagasse, cotton linter, cotton, miscanthus, grass, flax, hemp, jute, kenaf, bamboo, ramie and sisal, beets, fruits, tomato stems, and agricultural materials, such as bagasse, cotton linter and cotton, miscanthus, grass, hemp fiber and tomato chloroplasts. Other substrates include paper, paperboard, fibers, molded fibers, fibrils, cellulose fibers, regenerated cellulose, aramid, glass, carbon, polyester, wool, silk, and combinations thereof. Non-cellulose substrates can be, for example, aramid, glass, carbon, polyester, wool, silk, and combinations thereof.

[0044] In some aspects of this method, the substrate may be in the form of fiber, paper, paperboard, molded fiber articles (e.g., thick-walled, transfer, thermoformed (thin-walled) and processed articles), and molded paper / paperboard articles.

[0045] In some other aspects of the method, the substrate may also be selected from a nanocellulose, which is selected from microfibrillated cellulose (MFC), cellulose microfibrils (CMF), nanofibrillated cellulose (NFC), cellulose nanofibers (CNF), microcrystalline cellulose (MCC), cellulose microcrystals (CMC), nanocrystalline cellulose (NCC), cellulose nanocrystals (CNC), and combinations thereof.

[0046] In some other aspects of the method, the method includes providing a substrate having a three-dimensional (3D) structure of fibers, fibrils, and / or paper, wherein the fibers, fibrils, and / or paper are present in a network defining a plurality of air pores. In this regard, a composition is disposed on or applied to the surface of the substrate to coat the fibers, fibrils, and / or paper, thereby reducing or eliminating air pores in the substrate having a three-dimensional structure.

[0047] In other aspects of the method, the composition is applied or arranged on the surface of the fiber and / or the substrate by any technique suitable for dispensing liquid formulations onto dry fibers / paper / paperboard, such as spraying, dipping, brushing, and combinations thereof.

[0048] Finally, an article made by the above method is provided. Example

[0049] Example 1 – Preparation of Barrier Formulation In the first step, suspensions of microfibrillated cellulose (MFC) (0.5–1.5% by weight) and microcrystalline cellulose (MCC) (0.5–6.0% by weight) are prepared using an Ultra Turrax mixer by diluting the concentrated microfibrillated cellulose (MFC) and microcrystalline cellulose (MCC) pastes separately with water to the desired concentrations. The pH of the MFC and MCC suspensions is adjusted to 6.5–8.5 as needed.

[0050] In the second step, 200 µL of AKD aqueous dispersion (dry matter content of approximately 20% by weight) sizing agent is added to the MFC and MCC suspension prepared in the first step, and the suspension is mixed at 500 to 5000 rpm for 1 minute to produce a barrier composition to be applied to the substrate.

[0051] The composition is sprayed onto the surface of cellulose fibers in a dry molding process. The coated substrate or article is then cured at a temperature of 100°C to 150°C for 1 to 10 hours.

[0052] Example 2 – MFC as a carrier polymer for AKD sizing 0.5% by weight of AKD dispersion (approximately 20% by weight dry matter) was mixed with 20 g, 40 g, and 80 g of microfibrillated cellulose samples (1.3% by weight MFC, pH 6.5). The suspensions were mixed in a standard laboratory mixer and sprayed onto the surface of a fluffy cellulose mat (14 cm²) using an air-assisted spray gun. The sample was sprayed onto a 14 cm, 600 gsm plate. After spraying, the sample was dried in an oven at 105 °C for 5 minutes. After drying, the sample was flattened at 150 °C with a force of 10 metric tons for 5 minutes using a Carver press. A reference sample was also prepared using 40 g of water (pH 6.5) as a carrier without MFC for comparison. At the end of the process, post-curing was performed at 120 °C for 2 hours. The percentage of bound AKD and the percentage of recovered AKD / added AKD were determined by gas chromatography-mass spectrometry (GC / MS), and the results are shown in Table 1 below.

[0053] Table 1 – Percentage of Combined AKD and Percentage of Recycled AKD / Added AKD

[0054] The results showed that: 1) the percentage of bound AKD increased with the increase of MFC addition; and 2) the percentage of recovered AKD / added AKD was not improved when MFC was used as the carrier.

[0055] Example 3 – MCC as a carrier polymer for AKD sizing 0.5 wt% AKD dispersion (approximately 20 wt% dry matter content) was added to 40 g (6.0 wt% MCC, pH 8.0). The mixture was thoroughly mixed and sprayed onto the surface of a fluffy cellulose mat (14 cm × 14 cm, 600 gsm) using an air-assisted spray gun. After spraying, the sample was dried in an oven at 105 °C for 5 minutes. After drying, the sample was flattened using a carver press at 150 °C with a force of 10 metric tons for 5 minutes. A reference sample was also prepared using 40 g of water (pH 6.5) as a carrier, and the mixture was MFC-free. Post-curing was performed for 2 hours, and the percentage of bound AKD and the percentage of recovered AKD / added AKD are shown in Table 2 below.

[0056] Table 2 – Percentage of Combined AKD and Percentage of Recycled AKD / Added AKD

[0057] The results showed that: 1) when MCC was added as a carrier, the percentage of bound AKD increased to 43%; 2) the effect of 40 g of 6.0% MCC on the percentage of bound AKD was almost equivalent to that of 80 g of 1.3% MFC; and 3) the addition of MCC showed a positive effect on the percentage of recovered AKD / added AKD. Furthermore, considering that MCC has lower cost and lower viscosity compared to MFC, using MCC as a carrier system for AKD sizing agents shows more advantages over MFC (i.e. lower cost and less water loss when introducing dry molding process).

[0058] The combination of MFC and MCC provides a synergistic effect on the combined percentage of AKD and the AKD recovery rate, and adding 20g of 6% MCC on top of 20g of 1.3% MFC increases the combined percentage of AKD and the percentage of recovered AKD / added AKD by 60% and 89%, respectively.

[0059] When MFC and / or MCC are used as carrier polymers, the bound AKD increases to 66%. When MCC is used as the carrier polymer, the recovered AKD (i.e., recovered AKD / 100% added AKD) increases by 51%, indicating an improved distribution of AKD in the molded article.

[0060] While at least one exemplary embodiment has been presented in the foregoing detailed description and examples of the subject matter of this invention, it should be understood that numerous variations exist. It should also be understood that the exemplary embodiments are merely examples and are not intended to limit the scope, applicability, or configuration of the subject matter of this invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient roadmap for implementing exemplary embodiments of the subject matter of this invention. It should be understood that various changes can be made to the function and arrangement of the elements described in the exemplary embodiments without departing from the scope of the subject matter of this invention as set forth in the appended claims.

Claims

1. A barrier composition comprising: - An aqueous dispersion containing one or more functional additives, and - One or more nanocelluloses.

2. The barrier composition according to claim 1, wherein each of the one or more functional additives is selected from sizing agents, barrier agents, and combinations thereof.

3. The barrier composition according to claim 1 or 2, wherein the functional additive is a sizing agent selected from alkyl ketene dimer (AKD), alkenyl ketene dimer (AnKD), alkenyl succinic anhydride (ASA), rosin, and combinations thereof.

4. The barrier composition according to any one of claims 1 to 3, wherein the sizing agent is present in the barrier composition in an amount of about 0.01 weight percent to about 50 weight percent, or in an amount of about 0.01 weight percent to about 15 weight percent.

5. The barrier composition according to any one of claims 1 to 4, wherein the functional additive is a barrier agent selected from wax dispersions, latexes, natural polymer solutions, polymer dispersions, and combinations thereof.

6. The barrier composition according to any one of claims 1 to 5, wherein the barrier agent is present in the barrier composition in an amount greater than 0% to about 50% by weight, or in an amount of about 0.5% to about 30% by weight.

7. The barrier composition according to any one of claims 1 to 6, wherein the nanocellulose is selected from microfibrillated cellulose (MFC), cellulose microfibrils (CMF), nanofibrillated cellulose (NFC), cellulose nanofibers (CNF), microcrystalline cellulose (MCC), cellulose microcrystals (CMC), nanocrystalline cellulose (NCC), cellulose nanocrystals (CNC), and combinations thereof.

8. The barrier composition according to any one of claims 1 to 7, wherein the nanocellulose is present in the barrier composition in an amount of about 5% to about 99.9% by weight, or in an amount of about 10% to about 85% by weight, or in an amount of about 20% to about 70% by weight.

9. The barrier composition according to any one of claims 1 to 8, wherein the nanocellulose is present in a suspension or paste having a pH of about 5 to about 10 or about 5.5 to about 8.

5.

10. The barrier composition according to any one of claims 1 to 9, wherein the nanocellulose has a BET specific surface area of ​​at least about 5 m² / g, or at least about 10 m² / g.

11. The barrier composition according to any one of claims 1 to 10, wherein the average fiber width of the nanocellulose is less than about 1 micrometer or less than about 0.1 micrometer.

12. The barrier composition according to any one of claims 1 to 11, wherein the nanocellulose is present in a suspension or paste.

13. The barrier composition according to any one of claims 1 to 12, wherein the nanocellulose and the functional adjuvant are present in a dry matter mass ratio greater than about 1:1 or greater than about 10:1 to 1:

10.

14. The barrier composition according to any one of claims 1 to 13, further comprising a thermoplastic polymer selected from hydrocarbon resins, polypropylene and propylene copolymers, polyethylene and ethylene copolymers, polystyrene and styrene copolymers, polyesters, styrene-maleic anhydride copolymers and their salts, and combinations thereof.

15. A method for improving the retention, reactivity, and / or distribution of functional additives disposed on a fiber surface and / or substrate, the method comprising the steps of: - The substrate is provided having a substrate surface and including fibers having a fiber surface; as well as - The barrier composition according to claim 1 is disposed on the surface of the fiber and / or the surface of the substrate, and is in direct contact with the surface of the fiber and / or the surface of the substrate.

16. The method of claim 15, wherein the substrate is a dry-molded article and / or includes raw materials and / or intermediate materials for dry molding or dry forming processes.

17. The method of claim 15 or 16, wherein the composition is applied to the fiber surface and / or the substrate by spraying, dipping, brushing or any other technique to apply the barrier composition to the substrate.

18. The method according to any one of claims 15 to 17, wherein the substrate is selected from non-cellulose and cellulose fiber-based materials.

19. The substrate according to any one of claims 15 to 18, wherein the substrate comprises a three-dimensional (3D) structure of fibers, fibrils and / or paper, wherein the fibers, fibrils and / or paper are present in a network defining a plurality of air pores.

20. The article made by the method according to claim 15.

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