Method of forming a fire-retardant paper product or board product

Abstract

A method of forming a fire-retardant paper product or board product, includes saturating a paper with a liquid fire-retardant solution to form a saturated paper, processing the saturated paper to remove liquid and volatiles associated with the fire-retardant solution to form a fire-retardant paper, saturating the fire-retardant paper with a resin product to form a resin-infused fire-retardant paper, the resin product and the fire-retardant solution forming a non-intumescent composition, and processing the resin-infused fire-retardant paper to remove liquid and volatiles associated with the resin product to form a resin-treated non-intumescent fire-retardant paper product. Other associated methods are also provided.

Description

[0001] METHOD OF FORMING A FIRE-RETARDANT PAPER PRODUCT OR BOARD PRODUCT

[0002] BACKGROUND

[0003] Field of the Disclosure

[0004] Aspects of the present disclosure are directed to paper products and / or board products and, more particularly, a method of forming a fire-retardant paper product or board product, such as a fire-retardant paper product or a fire-retardant laminated board product.

[0005] Disclosure of Related Art

[0006] Some wood panel manufacturers add fire protection measures to the panel board by incorporating fire-retardant chemicals in the wood used to make the panel board. Such a process may be effective, but also can be relatively expensive, e.g., adding 50% to 100% to the produced cost of the fire-resistant panel boards as compared to non-fire-resistant panel boards. For example, fire-retardant Medium-Density Fiberboard (MDF) is currently produced incorporating the fire-retardant in the manufacturing process. Usually, such a manufacturing process involves adding about 7-11% dry fire-retardant (FR) per dry wood mass to produce a Euroclass B FR MDF board. Adding the FR in the manufacturing process, however, may adversely affect the quality of the MDF board, for example, resulting in poor internal bond strengths (IBs), requiring higher resin (e.g., MUF) addition (e.g., the resin may also be more expensive, as in the case where resins with high melamine content (>10%) are needed for FR board production, whereas non-FR boards are made with melamine-free resins or resins having in most cases less than 5% melamine), slowing the speed of the manufacturing line, etc.

[0007] An alternative approach for forming a fire-resistant panel board could be to coat or cover the surfaces of the panel board with a material which protects the panel board. Such a coating may be a fire-protecting paint, or such a cover could be a fire-resistant cover sheet.

[0008] Within the cellulose wood panel industry, wherein the produced wood panels include particle board, MDF and OSB board products, some producers have a requirement for enhancing fire-resistance performance through use of a surface-applied paper-based facing material to the wood panel. One challenge in meeting this requirement, however, is that current paper-facing solutions, which are predominantly decorative, may become stained and / or aesthetically unacceptable upon exposure to the fire-retardant treatment chemical and treatment process. In general, for a cellulose wood-panel producer to achieve a European Fire Rating such a producer is required to either a) create a board using fire-retardant chemistry in the production process, which ensures the board produced has fire protection measures; or b) apply a surface treatment to the board to provide the fire protection performance. Option a) often requires substantial capital investment and requires that the product be produced specifically for fire performance. This in turn creates a stock cost. It also limits the service level for delivery since products are often produced to order. Option b) allows for the use of standard production boards; however, this option does not allow for decorative faced products since the decorative facer (e.g., paper) will likely be adversely impacted by the application of the coating.

[0009] One benefit of Option b) is that a producer may use stock (i.e., standard non-FR) boards and apply the FR paper-facing the non-FR boards when FR performance is required, therefore providing a process for achieving an FR board that can be accomplished at a lower cost. Such a process can be readily undertaken by most cellulose board producers, since much of the particle board and MDF is already formed with paper-facing (e.g., with a veneer or other thin facing) for furniture and flooring applications. However, production issues may include, for example, negative interaction of the FR with the paper-facing, negative interaction of the FR with the resin adhesive chemistry, and difficulties with the implementation of the FR element in the application / production process.

[0010] As such, there exists a need for an improved process for producing fire-retardant paper products and / or board products.

[0011] SUMMARY OF THE DISCLOSURE

[0012] The above and other needs are met by aspects of the present disclosure which, in one aspect, provides a method of forming a fire-retardant paper product or board product. Such a method comprises saturating a paper with a liquid fire-retardant solution to form a saturated paper; processing the saturated paper to remove liquid and volatiles associated with the fire- retardant solution to form a fire-retardant paper; saturating the fire-retardant paper with a resin product to form a resin-infused fire-retardant paper, the resin product and the fire- retardant solution forming a non-intumescent composition; and processing the resin-infused fire-retardant paper to remove liquid and volatiles associated with the resin product to form a resin-treated non-intumescent fire-retardant paper product.

[0013] Another aspect provides a method of forming a fire-retardant paper product or board product, wherein said method comprises saturating a paper with a mixture comprising a liquid fire-retardant solution and a resin product, to form a saturated paper, the mixture being a non-intumescent composition; and processing the saturated paper to remove liquid and volatiles associated with the mixture to form a resin-treated non-intumescent fire-retardant paper product.

[0014] The present disclosure thus includes, without limitation, the following example embodiments:

[0015] Example Embodiment 1: A method of forming a fire-retardant paper product or board product, said method comprising saturating a paper with a liquid fire-retardant solution to form a saturated paper; processing the saturated paper to remove liquid and volatiles associated with the fire-retardant solution to form a fire-retardant paper; saturating the fire- retardant paper with a resin product to form a resin-infused fire-retardant paper, the resin product and the fire-retardant solution forming a non-intumescent composition; and processing the resin-infused fire-retardant paper to remove liquid and volatiles associated with the resin product to form a resin-treated non-intumescent fire-retardant paper product.

[0016] Example Embodiment 2: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper having a basis weight of at least 150 kg / m2with the liquid fire-retardant solution.

[0017] Example Embodiment 3: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper comprising one or more layers of paper stock with the liquid fire-retardant solution.

[0018] Example Embodiment 4: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper comprising a kraft paper, a paperboard, or a cardboard with the liquid fire-retardant solution.

[0019] Example Embodiment 5: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper with the liquid fire-retardant solution having a fire-retardant solids content of at least 45%.

[0020] Example Embodiment 6: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises directing the saturated paper through a roll press to remove excess liquid from the saturated paper.

[0021] Example Embodiment 7: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises heating the saturated paper to a temperature of at most 130°C for at most 1 minute to remove at least 85% of volatiles from the saturated paper.

[0022] Example Embodiment 8: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises processing the saturated paper to remove excess liquid and volatiles from the saturated paper and such that at least 40% of the fire-retardant solids content of the fire-retardant solution is retained in the fire-retardant paper.

[0023] Example Embodiment 9: The method of any preceding example embodiment, or combinations thereof, wherein saturating the fire-retardant paper with the resin product comprises saturating the fire-retardant paper with the resin product including a ureaformaldehyde resin, a phenol-formaldehyde resin, a melamine-formaldehyde resin or a melamine-urea-formaldehyde resin to form the resin-infused fire-retardant paper.

[0024] Example Embodiment 10: The method of any preceding example embodiment, or combinations thereof, wherein processing the resin-infused fire-retardant paper comprises directing the resin-infused fire-retardant paper through a roll press to remove excess resin product from the resin-infused non-intumescent fire-retardant paper.

[0025] Example Embodiment 11: The method of any preceding example embodiment, or combinations thereof, wherein processing the resin-infused fire-retardant paper comprises heating the resin-infused fire-retardant paper to a temperature of at most 130°C for at most 1 minute to remove at least 85% of volatiles from the resin-infused non-intumescent fire- retardant paper.

[0026] Example Embodiment 12: The method of any preceding example embodiment, or combinations thereof, wherein processing the resin-infused fire-retardant paper comprises processing the resin-infused fire-retardant paper to remove excess resin and volatiles from the resin-infused fire-retardant paper and such that the resin product is retained in the resin- treated non-intumescent fire-retardant paper.

[0027] Example Embodiment 13: The method of any preceding example embodiment, or combinations thereof, comprising arranging a layer of the resin-treated non-intumescent fire- retardant paper product between a layer of a decor paper and a layer of a board product such that the resin-treated non-intumescent fire-retardant paper product is in direct contact with the layer of the decor paper and the layer of the board product; and laminating the layers together to form a non-intumescent fire-retardant laminated board product.

[0028] Example Embodiment 14: The method of any preceding example embodiment, or combinations thereof, wherein laminating the layers comprises heating the layers to a temperature of at least 200°C.

[0029] Example Embodiment 15: The method of any preceding example embodiment, or combinations thereof, wherein laminating the layers comprises pressing the layers at a pressure of at least 30 kg / m2

[0030] Example Embodiment 16: The method of any preceding example embodiment, or combinations thereof, wherein laminating the layers together comprises applying heat and compression to the layers for at least 150 seconds to laminate the layers together.

[0031] Example Embodiment 17: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper with the liquid fire-retarding solution comprises saturating the paper with the liquid fire-retarding solution including a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, an aluminum compound, a magnesium compound, a bromine compound, or combinations thereof.

[0032] Example Embodiment 18: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper with the liquid fire-retarding solution comprises saturating the paper with the liquid fire-retarding solution including a borate compound, boric acid, an inorganic hydrate, a polyphosphate compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tri-potassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof.

[0033] Example Embodiment 19: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper with the liquid fire-retarding solution comprises saturating the paper with the liquid fire-retarding solution comprising a non- intumescent composition or an element of non-intumescent composition.

[0034] Example Embodiment 20: The method of any preceding example embodiment, or combinations thereof, wherein saturating the fire-retardant paper with the resin product comprises saturating the fire-retardant paper with the resin product comprising a non- intumescent composition or an element of a non-intumescent composition.

[0035] Example Embodiment 21: A method of forming a fire-retardant paper product or board product, said method comprising saturating a paper with a mixture comprising a liquid fire-retardant solution and a resin product, to form a saturated paper, the mixture being a non- intumescent composition; and processing the saturated paper to remove liquid and volatiles associated with the mixture to form a resin-treated non-intumescent fire-retardant paper product.

[0036] Example Embodiment 22: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper having a basis weight of at least 150 kg / m2with the mixture.

[0037] Example Embodiment 23: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper comprising one or more layers of paper stock with the mixture.

[0038] Example Embodiment 24: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper comprising a kraft paper, a paperboard, or a cardboard with the mixture.

[0039] Example Embodiment 25: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper with the mixture, the liquid fire-retardant solution of the mixture having a fire-retardant solids content of at least 45%.

[0040] Example Embodiment 26: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises directing the saturated paper through a roll press to remove excess liquid or excess resin from the saturated paper.

[0041] Example Embodiment 27: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises heating the saturated paper to a temperature of at most 130°C for at most 1 minute to remove at least 85% of volatiles from the saturated paper.

[0042] Example Embodiment 28: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises processing the saturated paper to remove excess liquid and volatiles from the saturated paper and such that at least 40% of the fire-retardant solids content of the fire-retardant solution of the mixture is retained in the resin-treated non-intumescent fire-retardant paper product.

[0043] Example Embodiment 29: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper comprises saturating the paper with the resin product of the mixture comprising a urea-formaldehyde resin, a phenol-formaldehyde resin, a melamine-formaldehyde resin or a melamine-urea-formaldehyde resin.

[0044] Example Embodiment 30: The method of any preceding example embodiment, or combinations thereof, wherein processing the saturated paper comprises processing the saturated paper to remove excess resin and volatiles therefrom and such that the resin product of the mixture is retained in the resin-treated non-intumescent fire-retardant paper product.

[0045] Example Embodiment 31: The method of any preceding example embodiment, or combinations thereof, comprising arranging a layer of the resin-treated non-intumescent fire- retardant paper product between a layer of a decor paper and a layer of a board product such that the resin-treated non-intumescent fire-retardant paper product is in direct contact with the layer of the decor paper and the layer of the board product; and laminating the layers together to form a non-intumescent fire-retardant laminated board product.

[0046] Example Embodiment 32: The method of any preceding example embodiment, or combinations thereof, wherein laminating the layers comprises heating the layers to a temperature of at least 200°C.

[0047] Example Embodiment 33: The method of any preceding example embodiment, or combinations thereof, wherein laminating the layers comprises pressing the layers at a pressure of at least 30 kg / m2

[0048] Example Embodiment 34: The method of any preceding example embodiment, or combinations thereof, wherein laminating the layers together comprises applying heat and compression to the layers for at least 150 seconds to laminate the layers together.

[0049] Example Embodiment 35: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper with the mixture comprises saturating the paper with the mixture, the liquid fire-retarding solution of the mixture including a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, a borate compound, an aluminum compound, a magnesium compound, a bromine compound, or combinations thereof.

[0050] Example Embodiment 36: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper with the mixture comprises saturating the paper with the mixture including boric acid, an inorganic hydrate, a polyphosphate compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tri-potassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof.

[0051] Example Embodiment 37: The method of any preceding example embodiment, or combinations thereof, wherein saturating the paper with the mixture comprises saturating the paper with the mixture, the liquid fire-retarding solution of the mixture comprising a non- intumescent composition or an element of non-intumescent composition.

[0052] Example Embodiment 38: The method of any preceding example embodiment, or combinations thereof, wherein saturating the fire-retardant paper with the mixture comprises saturating the fire-retardant paper with the mixture, the resin product of the mixture comprising a non-intumescent composition or an element of a non-intumescent composition.

[0053] These and other features, aspects, and advantages of the present disclosure will be apparent from a reading of the following detailed description together with the accompanying drawings, which are briefly described below. The present disclosure includes any combination of two, three, four, or more features or elements set forth in this disclosure, regardless of whether such features or elements are expressly combined or otherwise recited in a specific embodiment description herein. This disclosure is intended to be read holistically such that any separable features or elements of the disclosure, in any of its aspects and embodiments, should be viewed as intended, namely to be combinable, unless the context of the disclosure clearly dictates otherwise.

[0054] It will be appreciated that the summary herein is provided merely for purposes of summarizing some example aspects so as to provide a basic understanding of the disclosure. As such, it will be appreciated that the above-described example aspects are merely examples and should not be construed to narrow the scope or spirit of the disclosure in any way. It will be appreciated that the scope of the disclosure encompasses many potential aspects, some of which will be further described below, in addition to those herein summarized. Further, other aspects and advantages of such aspects disclosed herein will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described aspects.

[0055] DESCRIPTION OF THE DRAWINGS

[0056] Having thus described the disclosure in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

[0057] FIG. 1 schematically illustrates a method of forming a fire-retardant paper product or board product, according to one aspect of the present disclosure; and

[0058] FIG. 2 schematically illustrates a method of forming a fire-retardant paper product or board product, according to another aspect of the present disclosure.

[0059] DETAILED DESCRIPTION

[0060] The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the disclosures are shown. Indeed, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

[0061] Aspects of the present disclosure are directed to a method of forming a fire-retardant paper product or board product, as shown, for example, in FIG. 1. Such a method comprises saturating a paper with a liquid fire-retardant solution to form a saturated paper (Block 110); processing the saturated paper to remove liquid and volatiles associated with the fire- retardant solution to form a fire-retardant paper (Block 120); saturating the fire-retardant paper with a resin product to form a resin-infused fire-retardant paper, wherein the resin product and the fire-retardant solution form a non-intumescent composition (Block 130); and processing the resin-infused fire-retardant paper to remove liquid and volatiles associated with the resin product to form a resin-treated non-intumescent fire-retardant paper product (Block 140).

[0062] In some aspects, the paper having a basis weight of at least 150 kg / m2is saturated with the liquid fire-retardant solution. In other aspects, the paper comprising one or more layers of paper stock is saturated with the liquid fire-retardant solution. In still other aspects, the paper comprising a kraft paper, a paperboard, or a cardboard is saturated with the liquid fire-retardant solution. In further aspects, the liquid fire-retardant solution has a fire-retardant solids content of at least 45%. In still further aspects, the liquid fire-retardant (or fireretarding) solution combined with and absorbed by the paper may comprise a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, a borate compound, boric acid, an inorganic hydrate, a bromine compound, a polyphosphate compound, an aluminum compound, a magnesium compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tri-potassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof. In such aspects, the liquid fire-retardant (or fire-retarding) solution combined with and absorbed by the paper may comprise a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, an aluminum compound, a magnesium compound, a bromine compound, or combinations thereof, and / or the liquid fire-retardant (or fire-retarding) solution combined with and absorbed by the paper may comprise a borate compound, boric acid, an inorganic hydrate, a polyphosphate compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tri-potassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof.

[0063] The liquid fire-retardant solution and / or the resin product, in some aspects, are not and do not include an intumescent compound or an element of an intumescent compound, and any mixture of or interaction between the fire-retardant solution and the resin product do not result in an intumescent composition. Thus, the fire-retardant mechanism exhibited by the subsequently produced paper product and / or the board product is not by intumescence. Alternately stated, the fire-retardant solution, the resin product, or the mixture of the fire- retardant solution and the resin product implemented to saturate the paper, as disclosed herein, comprise a non-intumescent composition or an element of non-intumescent composition.

[0064] In some aspects, processing the saturated paper comprises directing the saturated paperboard through a roll press to remove excess liquid and / or volatiles from the saturated paper. That is, the saturated paper can be mechanically processed (e.g., by the application of pressure) to remove excess liquid and / or volatiles therefrom. In other aspects, the saturated paper can be processed or further processed by heating to a temperature of at most 130°C for at most 1 minute to remove excess liquid and / or volatiles (e.g., at least 85% of volatiles) from the saturated paper. In still other aspects, the saturated paper is processed to remove excess liquid and / or volatiles from the saturated paper and such that at least 40% of the fire-retardant solids content of the fire-retardant solution is retained in the non-intumescent fire-retardant paper.

[0065] One skilled in the art will appreciate that the liquid can be evaporated or otherwise removed from the saturated paper having the fire-retarding solution absorbed therein, in different appropriate manners. For example, the saturated paper having the fire-retarding solution absorbed therein may be mechanically pressed and / or heated to remove or evaporate the liquid. In other instances, the saturated paper having the fire-retarding solution absorbed therein may have the liquid evaporated therefrom by subjecting the saturated paper to infrared heating, microwave drying or any other suitable process to remove at least some of the liquid and / or volatiles from the fire-retarding solution absorbed by the saturated paper. That is, it may be sufficient to evaporate at least a portion or particular amount of the liquid from the fire-retarding solution such that precipitates of the increasingly concentrated (less liquid) fire-retarding solution, a more highly concentrated fire-retarding solution, and / or solids of the fire-retarding solution sufficiently remain within or otherwise remain engaged with the paper being FR-treated.

[0066] In some aspects, saturating the fire-retardant paper with a resin product to form a resin-infused fire-retardant paper comprises saturating the fire-retardant paper with the resin product, the resin product comprising a urea-formaldehyde resin, a phenol-formaldehyde resin, a melamine-formaldehyde resin or a melamine-urea-formaldehyde resin to form the resin-infused fire-retardant paper. In other aspects, the particular resin product is selected to avoid negative interaction of the selected fire-retardant solution with the resin adhesive chemistry.

[0067] To re-iterate, the fire-retardant solution and / or the resin product, in some aspects, are not and do not include an intumescent compound or an element of an intumescent compound, and any mixture of or interaction between the fire-retardant solution (or the solids of the fire- retardant solution) and the resin product do not result in an intumescent composition. Thus, the fire-retardant mechanism exhibited by the subsequently produced paper product and / or the board product is not by intumescence. Alternately stated, the fire-retardant solution, the resin product, or the mixture of the fire-retardant solution (or solids of the fire-retardant solution) and the resin product implemented to saturate the paper, as disclosed herein, comprise a non-intumescent composition or an element of non-intumescent composition.

[0068] In some aspects, processing the resin-infused fire-retardant paper comprises directing the resin-infused fire-retardant paper through a roll press to remove excess resin product and / or volatiles from the resin-infused fire-retardant paper. That is, the resin-infused fire- retardant paper can be mechanically processed (e.g., by the application of pressure) to remove excess resin and / or volatiles therefrom. In other aspects, the resin-infused fire-retardant paper can be processed or further processed by heating to a temperature of at most 130°C for at most 1 minute to remove volatiles from the resin-infused fire-retardant paper. In still other aspects, the resin-infused fire-retardant paper is processed to remove excess resin and / or volatiles from the resin-infused fire-retardant paper and such that the resin product is retained in the resin-treated non-intumescent fire-retardant paper product.

[0069] Other aspects of the present disclosure are directed to a method of forming a fire- retardant paper product or board product, as shown, for example, in FIG. 2. Such a method comprises saturating a paper with a mixture comprising a liquid fire-retardant solution and a resin product, to form a saturated paper, the mixture being a non-intumescent composition (Block 210); and processing the saturated paper to remove liquid and volatiles associated with the mixture to form a resin-treated non-intumescent fire-retardant paper product (Block 220).

[0070] In some aspects, the paper having a basis weight of at least 150 kg / m2is saturated with the mixture. In other aspects, the paper comprising one or more layers of paper stock is saturated with the mixture. In still other aspects, the paper comprising a kraft paper, a paperboard, or a cardboard is saturated with the mixture. In further aspects, the liquid fire- retardant solution of the mixture has a fire-retardant solids content of at least 45%. In still further aspects, the liquid fire-retardant (or fire-retarding) solution of the mixture combined with and absorbed by the paper may comprise a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, a borate compound, boric acid, an inorganic hydrate, a bromine compound, a polyphosphate compound, an aluminum compound, a magnesium compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tri-potassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof. In such aspects, the liquid fire-retardant (or fire-retarding) solution combined with and absorbed by the paper may comprise a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, an aluminum compound, a magnesium compound, a bromine compound, or combinations thereof, and / or the liquid fire- retardant (or fire-retarding) solution combined with and absorbed by the paper may comprise a borate compound, boric acid, an inorganic hydrate, a polyphosphate compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tripotassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof.

[0071] In some aspects, processing the saturated paper comprises directing the saturated paperboard through a roll press to remove excess liquid, excess resin, and / or volatiles thereof from the saturated paper. That is, the saturated paper can be mechanically processed (e.g., by the application of pressure) to remove excess liquid, excess resin, and / or volatiles therefrom. In other aspects, the saturated paper can be processed or further processed by heating to a temperature of at most 130°C for at most 1 minute to remove excess liquid, resin and / or volatiles (e.g., at least 85% of volatiles) from the saturated paper. In still other aspects, the saturated paper is processed to remove excess liquid and / or volatiles from the saturated paper and such that at least 40% of the fire-retardant solids content of the fire-retardant solution of the mixture is retained in the resin-treated non-intumescent fire-retardant paper product.

[0072] One skilled in the art will appreciate that liquid, resin, and / or volatiles can be evaporated or otherwise removed from the saturated paper having the mixture absorbed therein, in different appropriate manners. For example, the saturated paper having the mixture absorbed therein may be mechanically pressed and / or heated to remove or evaporate the liquid, resin, and / or volatiles. In other instances, the saturated paper having the mixture absorbed therein may have the liquid, resin, and / or volatiles evaporated therefrom by subjecting the saturated paper to infrared heating, micro wave drying or any other suitable process to remove at least some of the liquid, resin, and / or volatiles from the mixture absorbed by the saturated paper. That is, it may be sufficient to evaporate at least a portion or particular amount of the liquid, resin, and / or volatiles from the mixtures such that precipitates of the increasingly concentrated (less liquid) fire-retarding solution, a more highly concentrated fire-retarding solution, and / or solids of the fire-retarding solution and / or the resin sufficiently remain within or otherwise remain engaged with the paper being treated.

[0073] In some aspects, saturating the fire-retardant paper comprises saturating the fire- retardant paper with the mixture, wherein the resin product of the mixture comprises a ureaformaldehyde resin, a phenol-formaldehyde resin, a melamine-formaldehyde resin or a melamine-urea-formaldehyde resin. In other aspects, the particular resin product is selected to avoid negative interaction of the selected fire-retardant solution with the resin adhesive chemistry in the mixture.

[0074] In some aspects, the resin-infused fire-retardant paper is processed to remove excess resin and / or volatiles from the resin-infused non-intumescent fire-retardant paper and such that the resin product of the mixture is retained in the resin-treated non-intumescent fire- retardant paper product.

[0075] In some aspects, a method of forming a fire-retardant paper product or board product can comprise arranging a layer of the resin-treated non-intumescent fire-retardant paper product between a layer of a decor paper and a layer of a board product such that the resin- treated non-intumescent fire-retardant paper product is in direct contact with the layer of the decor paper and the layer of the board product (FIG. 1, Block 150; FIG. 2, Block 230); and laminating the layers together to form a non-intumescent fire-retardant laminated board product (FIG. 1, Block 160; FIG. 2, Block 240).

[0076] In some aspects, laminating the layers can include heating the layers to a temperature of at least 200°C and / or pressing the layers at a pressure of at least 30 kg / m2In other aspects, laminating the layers together comprises applying heat and compression (e.g., heating the layers to a temperature of at least 200°C and / or pressing the layers at a pressure of at least 30 kg / m2) to the layers for at least 150 seconds to laminate the layers together.

[0077] Example 1

[0078] A Euroclass B, Fire-Retardant (FR) laminated MDF board formed using FR-treated kraft paper on a standard non-FR MDF board involved the steps of:

[0079] 1. Submerging a kraft paper (weight >150kg / m2) in a FR solution bath (FR solid content > 46%) until the kraft paper is saturated.

[0080] 2. Directing the FR-treated (saturated) kraft paper through opposing wire rolls to remove excess liquid and then place in an oven at 130°C for 30 sec to remove volatiles (Dry FR pick up is > 40%).

[0081] 3. Submerging the dried FR-treated kraft paper in a 2ndbath with MF / MUF resin. 4. Directing the resin-treated (saturated) FR kraft paper through opposing wire rolls to remove excess resin and then place in an oven at 130°C for 30 sec to remove volatiles, (resin pickup after drying is 100%).

[0082] 5. Layering the resin-treated non-intumescent FR kraft paper between a standard non-FR decor paper (decor papers are specialty papers used to create quality finishes on wooden materials) and a standard non-FR MDF board.

[0083] 6. Processing the layered materials in a hot press (Temperature: 200°C, Pressure: 34 kg / cm2) for 160 sec.

[0084] The final product is a Euroclass B FR laminated MDF board product which is produced in a single laminating step, without adding the FR to the standard MDF board in the manufacturing process thereof, or in the lamination process.

[0085] Aspects of the present disclosure thus provide a technical solution wherein a non- intumescent fire-retardant (FR) treated backing paper (BP) layer having a resin material preapplied thereto can be layered between a board product (B) layer and a facer layer (e.g., a decorative paper (DP)), prior to all layers being laminated together in a single laminating step. The non-intumescent fire-retardant backing paper layer as the middle layer of the laminate thus provides an integral laminated non-intumescent fire-retardant board product with a customizable external layer (e.g., the decorative paper) and the structural strength of the underlying or inner layer (e.g., the board product). The non-intumescent FR backing paper having a fire-retardant performance allows the producer to offer the FR rating on decorative-faced finished goods, such as worktops, laminate flooring and commercial joinery.

[0086] Further, if a customizable external layer is desired on each side of the board product layer, a non-intumescent FR treated backing paper layer having the resin material pre-applied thereto can be layered on either side of the board product layer, and then a facer layer (e.g., a decorative paper) layered on the external surface of each backing paper layer (such that the five layers are arranged as DP-BP-B-BP-DP), before the layers are laminated together in a single laminating step.

[0087] This technical solution thus allows and provides a fire-retardant paper product or board product demonstrating improved non-intumescent fire performance, for example, by meeting European Fire Test standards, up to and including the highest European Fire Test standard - Euroclass B, without requiring a costly fire-rated cellulose panel (e.g., as the structural board product) that is obtained by fire-retardant treating the wood / cellulose of the cellulose panel itself. That is, the technical solution implements only the backing paper / kraft paper layer(s) of the laminate as the non-intumescent fire-retardant layer(s) (the remaining layers (e.g., the board product layer(s) and the facer layer(s)) do not require a fireretarding treatment or are otherwise not treated for fire-retardancy) which, in turn, imparts the fire-retardant property to the laminate. A person of ordinary skill in the art will appreciate, however, that the board product layer(s) and / or the facer layer(s) could also be treated for fire-retardancy, in addition to the backing paper layer(s), if necessary or desired.

[0088] Many modifications and other embodiments of the disclosures set forth herein will come to mind to one skilled in the art to which these disclosures pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the disclosures are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

THAT WHICH IS CLAIMED:

1. A method of forming a fire-retardant paper product, said method comprising: saturating a paper with a liquid fire-retardant solution to form a saturated paper; processing the saturated paper to remove liquid and volatiles associated with the fire- retardant solution to form a fire-retardant paper; saturating the fire-retardant paper with a resin product to form a resin-infused fire- retardant paper, the resin product and the fire-retardant solution forming a non-intumescent composition; and processing the resin-infused fire-retardant paper to remove liquid and volatiles associated with the resin product to form a resin-treated non-intumescent fire- retardant paper product.

2. The method of Claim 1, wherein saturating the paper comprises saturating the paper having a basis weight of at least 150 kg / m2with the liquid fire-retardant solution.

3. The method of Claim 1, wherein saturating the paper comprises saturating the paper comprising one or more layers of paper stock with the liquid fire-retardant solution.

4. The method of Claim 1, wherein saturating the paper comprises saturating the paper comprising a kraft paper, a paperboard, or a cardboard with the liquid fire-retardant solution.

5. The method of Claim 1, wherein saturating the paper comprises saturating the paper with the liquid fire-retardant solution having a fire-retardant solids content of at least 45%.

6. The method of Claim 1, wherein processing the saturated paper comprises directing the saturated paper through a roll press to remove excess liquid from the saturated paper.

7. The method of Claim 1, wherein processing the saturated paper comprises heating the saturated paper to a temperature of at most 130°C for at most 1 minute to remove at least 85% of volatiles from the saturated paper.

8. The method of Claim 1, wherein processing the saturated paper comprises processing the saturated paper to remove excess liquid and volatiles from the saturated paper and such that at least 40% of the fire-retardant solids content of the fire-retardant solution is retained in the fire-retardant paper.

9. The method of Claim 1, wherein saturating the fire-retardant paper with the resin product comprises saturating the fire-retardant paper with the resin product including a urea-formaldehyde resin, a phenol-formaldehyde resin, a melamine-formaldehyde resin or a melamine-urea-formaldehyde resin to form the resin-infused fire-retardant paper.

10. The method of Claim 1, wherein processing the resin-infused fire-retardant paper comprises directing the resin-infused fire-retardant paper through a roll press to remove excess resin product from the resin-infused non-intumescent fire-retardant paper.

11. The method of Claim 1, wherein processing the resin-infused fire-retardant paper comprises heating the resin-infused fire-retardant paper to a temperature of at most 130°C for at most 1 minute to remove at least 85% of volatiles from the resin-infused non- intumescent fire-retardant paper.

12. The method of Claim 1, wherein processing the resin-infused fire-retardant paper comprises processing the resin-infused fire-retardant paper to remove excess resin and volatiles from the resin-infused fire-retardant paper and such that the resin product is retained in the resin-treated non-intumescent fire-retardant paper.

13. The method of Claim 1, comprising: arranging a layer of the resin-treated non-intumescent fire-retardant paper product between a layer of a decor paper and a layer of a board product such that the resin-treated non-intumescent fire-retardant paper product is in direct contact with the layer of the decor paper and the layer of the board product; and laminating the layers together to form a non-intumescent fire-retardant laminated board product.

14. The method of Claim 13, wherein laminating the layers comprises heating thelayers to a temperature of at least 200°C.

15. The method of Claim 13, wherein laminating the layers comprises pressing the layers at a pressure of at least 30 kg / m216. The method of Claim 13, wherein laminating the layers together comprises applying heat and compression to the layers for at least 150 seconds to laminate the layers together.

17. The method of Claim 1, wherein saturating the paper with the liquid fireretarding solution comprises saturating the paper with the liquid fire-retarding solution including a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, an aluminum compound, a magnesium compound, a bromine compound, or combinations thereof.

18. The method of Claim 1, wherein saturating the paper with the liquid fireretarding solution comprises saturating the paper with the liquid fire-retarding solution including a borate compound, boric acid, an inorganic hydrate, a polyphosphate compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tripotassium citrate monohydrate, methyl bromide, methyl iodide, urea, or combinations thereof.

19. The method of Claim 1, wherein saturating the paper with the liquid fireretarding solution comprises saturating the paper with the liquid fire-retarding solution comprising a non-intumescent composition or an element of non-intumescent composition.

20. The method of Claim 1, wherein saturating the fire-retardant paper with the resin product comprises saturating the fire-retardant paper with the resin product comprising a non-intumescent composition or an element of anon-intumescent composition.

21. A method of forming a fire-retardant paper product, said method comprising: saturating a paper with a mixture comprising a liquid fire-retardant solution and a resin product, to form a saturated paper, the mixture being a non-intumescent composition; andprocessing the saturated paper to remove liquid and volatiles associated with the mixture to form a resin-treated non-intumescent fire-retardant paper product.

22. The method of Claim 21, wherein saturating the paper comprises saturating the paper having a basis weight of at least 150 kg / m2with the mixture.

23. The method of Claim 21, wherein saturating the paper comprises saturating the paper including one or more layers of paper stock with the mixture.

24. The method of Claim 21, wherein saturating the paper comprises saturating the paper comprising a kraft paper, a paperboard, or a cardboard with the mixture.

25. The method of Claim 21, wherein saturating the paper comprises saturating the paper with the mixture, the liquid fire-retardant solution of the mixture having a fire- retardant solids content of at least 45%.

26. The method of Claim 21, wherein processing the saturated paper comprises directing the saturated paper through a roll press to remove excess liquid or excess resin from the saturated paper.

27. The method of Claim 21, wherein processing the saturated paper comprises heating the saturated paper to a temperature of at most 130°C for at most 1 minute to remove at least 85% of volatiles from the saturated paper.

28. The method of Claim 21, wherein processing the saturated paper comprises processing the saturated paper to remove excess liquid and volatiles from the saturated paper and such that at least 40% of the fire-retardant solids content of the fire-retardant solution of the mixture is retained in the resin-treated non-intumescent fire-retardant paper product.

29. The method of Claim 21, wherein saturating the paper comprises saturating the paper with the resin product of the mixture comprising a urea-formaldehyde resin, a phenol-formaldehyde resin, a melamine-formaldehyde resin or a melamine-urea- formaldehyde resin.

30. The method of Claim 21, wherein processing the saturated paper comprises processing the saturated paper to remove excess resin and volatiles therefrom and such that the resin product of the mixture is retained in the resin-treated non-intumescent fire-retardant paper product.

31. The method of Claim 21, comprising: arranging a layer of the resin-treated non-intumescent fire-retardant paper product between a layer of a decor paper and a layer of a board product such that the resin-treated non-intumescent fire-retardant paper product is in direct contact with the layer of the decor paper and the layer of the board product; and laminating the layers together to form a non-intumescent fire-retardant laminated board product.

32. The method of Claim 31, wherein laminating the layers comprises heating the layers to a temperature of at least 200°C.

33. The method of Claim 31, wherein laminating the layers comprises pressing the layers at a pressure of at least 30 kg / m234. The method of Claim 31, wherein laminating the layers together comprises applying heat and compression to the layers for at least 150 seconds to laminate the layers together.

35. The method of Claim 21, wherein saturating the paper with the mixture comprises saturating the paper with the mixture, the liquid fire-retarding solution of the mixture including a boron compound, a phosphorus compound, a chlorine compound, a lithium compound, a fluorine compound, an antimony compound, an aluminum compound, a magnesium compound, a bromine compound, or combinations thereof.

36. The method of Claim 21, wherein saturating the paper with the mixture comprises saturating the paper with the mixture, the liquid fire-retarding solution of the mixture including a borate compound, boric acid, an inorganic hydrate, a polyphosphate compound, a phosphonium salt, a zirconium salt, ammonium phosphate, diammonium phosphate, tri-potassium citrate monohydrate, methyl bromide, methyl iodide, urea, orcombinations thereof.

37. The method of Claim 21, wherein saturating the paper with the mixture comprises saturating the paper with the mixture, the liquid fire-retarding solution of the mixture comprising a non-intumescent composition or an element of non-intumescent composition.

38. The method of Claim 21, wherein saturating the fire-retardant paper with the mixture comprises saturating the fire-retardant paper with the mixture, the resin product of the mixture comprising a non-intumescent composition or an element of a non-intumescent composition.

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