Waterproofing membrane with cross-laminated film

Abstract

A waterproof membrane includes first and second nonwoven layers, each nonwoven layer having first and second surfaces. A cross-laminated film layer is disposed between the first and second nonwoven layers. An adhesive layer is coated between the nonwoven layers and the cross-laminated film. Also disclosed are a method for manufacturing a waterproof membrane, a method for establishing a waterproof barrier between a substrate and a tile, and a flexible membrane for use on curved surfaces.

Description

[0001] This application is a divisional application of the invention patent application filed on June 16, 2014, with application number 201910570366.5 and entitled "Waterproof Membrane with Cross-Laminated Film". Furthermore, the invention patent application filed on June 16, 2014, with application number 201910570366.5 and entitled "Waterproof Membrane with Cross-Laminated Film", is a divisional application of the invention patent application filed on June 16, 2014, with international application number PCT / US2014 / 042511 and national application number 201480045478.4 and entitled "Waterproof Membrane with Cross-Laminated Film".

[0002] Cross-references to related applications This application claims the benefit and priority of U.S. Provisional Patent Application No. 61 / 836,750, filed June 19, 2013, the entire disclosure of which is incorporated herein by reference. Background Technology

[0003] The ability of a building structure, such as walls or floors, to be effectively waterproof is extremely important. Waterproofing is crucial to preventing moisture from penetrating and degrading the underlying substrate and structure.

[0004] In one instance, in areas like bathrooms and shower rooms where damp environments and moisture and / or water intrusion are possible, a waterproof surface is required between the tiles and the underlying substrate (e.g., wall or floor) and the supporting structure (e.g., studs). Water tends to seep behind tiled walls and the floor beneath, through the cement grout, and into the wall and floor substrate. If the underlying substrate is made of a water-resistant or perhaps even waterproof material, potential damage to the substrate and the underlying structure is minimized. For example, cement board or water-resistant plasterboard is commonly used as the substrate in areas such as shower rooms.

[0005] However, this material is not inherently waterproof and may deteriorate over time. Furthermore, in use, the material formed from the sheets can be cut, and seams are used where the sheets are placed together, such as along extended surfaces, at corners, and around openings, which exacerbates the possibility of water intrusion and degradation. In this respect, water and / or moisture may penetrate the substrate or seep through the base material and into the underlying structure unless waterproof elements are used across its entire surface to protect the base material.

[0006] Other materials are also known. For example, KERDI-BOARD, available from Schluter, is a multi-component waterproofing board for areas that may be exposed to high humidity. However, because it is a rigid structure that requires seams and cuts to accommodate long stretches of surfaces, corners, etc., the seams and seepage must be treated with waterproofing elements.

[0007] Therefore, there is a need for a waterproof element for use in high-humidity environments during new construction, remodeling, and renovation. Ideally, this element is flexible and in sheet or roll form. More ideally, this element is formed into a membrane that is flexible enough to allow use in corners, curved areas, etc., without the use of seams and joints. Even more ideally, this material has sufficient strength, for example, high strength, to prevent tearing and punctures when used, for example, on a construction site. Summary of the Invention

[0008] A membrane includes a first nonwoven layer having first and second surfaces, a cross-laminated film, a second nonwoven layer having first and second surfaces, and an adhesive layer located between the first nonwoven first surface and the cross-laminated film and between the second nonwoven first surface and the cross-laminated film.

[0009] Cross-laminated films can be oriented cross-laminated films. In one embodiment, the oriented cross-laminated film is a high-density polyethylene (HDPE) oriented cross-laminated film. In one embodiment, the HDPE oriented cross-laminated film has a thickness of approximately 3.0 millimeters.

[0010] The adhesive layer may be a polyolefin or a polyolefin copolymer or a blend thereof. In one embodiment, the adhesive layer is a propylene-based elastomer blend. One blend is a blend with low-density polyethylene (LDPE). In such a blend, the propylene-based elastomer may be present in about 10% to about 60% (by weight) of the adhesive layer blend, and may be about 25% (by weight) of the blend, and the LDPE may be present in about 40% to about 90% (by weight) of the adhesive layer blend, and may be about 75% (by weight) of the blend. The adhesive layer may be present or applied in a quantity of about 5 pounds per ream to about 20 pounds per ream, and may be about 7 pounds per ream to about 10 pounds per ream.

[0011] The nonwoven layer can be a polypropylene nonwoven fabric. The fabric can have a basis weight of about 0.5 ounces per square yard (osy) to about 4.0 osy, or about 0.9 osy.

[0012] The waterproof membrane can be formed as having first and second polypropylene nonwoven layers with first and second surfaces, an HDPE-oriented cross-laminated film layer, and an adhesive layer located between the first nonwoven first surface and the oriented cross-laminated film layer, and between the second nonwoven first surface and the oriented cross-laminated film layer. The adhesive layer can be a propylene-based elastomer or a blend of propylene-based elastomers.

[0013] Each of the first and second polypropylene nonwoven layers may have a basis weight of approximately 0.9 osy, the HDPE oriented cross-laminated film layer may have a thickness of approximately 3.0 mils, and the content of each adhesive layer may be approximately 7 to approximately 10 pounds per ream of film. In such a film, the adhesive layer is a blend of a propylene-based elastomer and LDPE, wherein the content of the propylene-based elastomer is approximately 25% by weight of the blend, and the content of LDPE is approximately 75% by weight of the blend.

[0014] A method of manufacturing a waterproof membrane includes adhering a cross-laminated film layer between first and second polypropylene nonwoven layers, each having first and second surfaces. In this method, the cross-laminated film layer may be an oriented cross-laminated film layer, such as an HDPE oriented cross-laminated film layer. In this method, the adhesion step may be performed by applying an adhesive layer between the first nonwoven layer and the oriented cross-laminated film, and by applying an adhesive layer between the second nonwoven layer and the oriented cross-laminated film.

[0015] The adhesion step may include laminating a first nonwoven layer to the oriented cross-laminated film layer on one side of the cross-laminated film layer, and laminating a second nonwoven layer to the oriented cross-laminated film layer on the opposite side of the cross-laminated film layer. The lamination step may be performed using extrusion lamination.

[0016] In one embodiment, a method for establishing a waterproof barrier between a substrate and a tiled wall includes coating a waterproof membrane onto the substrate, the waterproof membrane having a first nonwoven layer with first and second surfaces, a cross-laminated film layer, a second nonwoven layer with first and second surfaces, and an adhesive layer between the first nonwoven first surface and the cross-laminated film, and an adhesive layer between the second nonwoven first surface and the cross-laminated film. Tiles are then coated onto the waterproof membrane. The method may include the steps of: applying a coating of thin-set adhesive to the substrate; applying the waterproof membrane to the thin-set adhesive; applying a second thin coating to the membrane; and applying the tiles to the coating of the thin-set adhesive.

[0017] These and other features and advantages of the invention will become apparent from the following detailed description in conjunction with the claims. Attached Figure Description

[0018] The benefits and advantages of this invention will become more apparent to those skilled in the art after reviewing the following detailed description and accompanying drawings, wherein: Figure 1 A cross-sectional view of a waterproof membrane with cross-laminated films; and Figure 2 A cross-sectional view of an exemplary use of a film when applying tiles to a wall or floor. Detailed Implementation

[0019] While this disclosure is readily implemented in various forms, one or more embodiments are shown in the accompanying drawings and will be described thereafter. It is to be understood that this disclosure should be considered as illustrative and is not intended to be limited to the particular embodiments or the embodiments shown.

[0020] Figure 1 A waterproof membrane 10 with a cross-laminated film is shown. An embodiment of membrane 10 is formed as a laminate with a structure of ABCBA, wherein A is a nonwoven sheet 12, B is a polymer bonding resin layer 14 and C is an oriented cross-laminated film 16.

[0021] A nonwoven sheet 12 is a polypropylene (PP) nonwoven fabric with a basis weight of approximately 0.5 osy to approximately 4.0 osy, and may be approximately 0.9 osy. A suitable material is Elite 100 Lt. Grey #49623, available from Hanes Companies, Inc. This material has a basis weight of approximately 0.9 ounces (osy) per square yard per ASTM D 3776M-09A, an elongation of approximately 75% in the machine direction and approximately 85% in the transverse direction per ASTM D 5034-09, a tensile strength of approximately 86 N / 2.54 cm in the machine direction and approximately 70 N / 2.54 cm in the transverse direction per ASTM D 5034-09, and a tear strength of approximately 7 lbs in the machine direction and 9.7 lbs in the transverse direction per ASTM D 5733-09.

[0022] Other suitable materials for the nonwoven sheet 12 include polyethylene terephthalate (PET), for example, PET point-bonded nonwoven materials. Other suitable materials will be recognized by those skilled in the art.

[0023] The polymeric adhesive layer 14 provides adhesion between the nonwoven sheet 12 and the oriented cross-laminated film 16 (as discussed below). The adhesive layer can be a polyolefin or a polyolefin copolymer or a blend thereof. In one embodiment, the adhesive layer is a blend of a propylene-based elastomer. One blend is a blend with low-density polyethylene (LDPE). In such a blend, the propylene-based elastomer content can be from about 10% to about 60% of the weight of the adhesive layer blend and can be about 25% of the weight of the blend, and the LDPE content can be from about 40% to about 90% of the weight of the adhesive layer blend and can be about 75% of the weight of the blend. The adhesive layer content can be from about 5 pounds per ream to about 20 pounds per ream, and can be from about 7 pounds per ream to about 10 pounds per ream. A suitable LDPE is available from Westlake Chemical Corporation under the name EC808. Other suitable materials include LyondellBasell NA214.

[0024] A suitable propylene-based elastomer is available from Exxon-Mobil Chemical as Vistamaxx™ 6202. Other suitable materials include thermoplastic polyolefins such as Adflex Z 108, which are available from LyondellBasell Industries. In one embodiment, adhesive layer 14 is made of a blend of about 75% (by weight) LDPE and 25% (by weight) propylene-based elastomer. Specific formulations may vary in a manner recognized by those skilled in the art.

[0025] A suitable cross-laminated film 16 is an oriented cross-laminated polyolefin, such as a high-density polyethylene (HDPE) film available from VALERON® Strength Films of Houston, Texas. The oriented cross-laminated HDPE film 16 has a thickness of approximately 3.0 mils. VALERON® Strength Films' branded film is an HDPE material made from a cross-laminated composite of two film layers or stacks, each layer being extruded and beveled in a continuous spiral to achieve a molecular orientation between 1 degree and 89 degrees to the machine direction. The beveled film stacks are then cross-laminated, and may, but not necessarily, utilize an adhesive or polymer between the film layers to form a woven fabric. Such a film is disclosed and described in U.S. Patent Serial No. 6,284,344 to Bames, which is jointly assigned with this application and incorporated herein by reference. Other materials, such as polyethylene terephthalate (PET), polyolefins including polypropylene (PP), polyamides, and co-extruded polymeric materials, are considered as potential candidates for the oriented cross-laminated film 16. Such films, such as VALERON ®Strength Films brand films may be provided as materials comprising two or more layers; such films are within the scope and spirit of this disclosure.

[0026] In this film 10, the nonwoven layer 12 is a polypropylene nonwoven material with a basis weight of approximately 0.9 osy, and as mentioned above, the adhesive layer is a blend of 75% (by weight) LDPE and 25% (by weight) propylene elastomer. Each adhesive layer 14 contains approximately 7-10 pounds per ream, and in one embodiment, approximately 8 pounds per ream of film 10, and the oriented cross-laminated film 16 is a 3.0 mil VALERON® Strength Films brand film.

[0027] It is conceivable that membrane 10 will be manufactured using a lamination process. For example, in an extrusion lamination process, in the first lamination, nonwoven material 12a is laminated into an oriented cross-laminated film 16 using a blend of adhesive layer 14a at approximately 7 to 10 pounds per ream to form the partially shaped film. In the second lamination, nonwoven material 12b is laminated to the opposite side of the oriented cross-laminated film 16, which again uses a blend of adhesive layer 14b at approximately 7 to 10 pounds per ream to form the aforementioned ABCBA structure. Other processes and other lamination techniques, including adhesives, solvent-free adhesives, etc., are also conceivable.

[0028] It has also been found that the adhesive layer 14 can be made of essentially 100% acrylic elastomer (e.g., 100% Vistamacxx™ 6202) and the film 10 is also formed to have such functionality.

[0029] In one of the considered uses, such as in Figure 2 As shown, membrane 10 is used as a waterproof membrane behind wall and floor tiles T in a shower room or under a floor for waterproofing or preventing reflective cracking. Membrane 10 is applied to the substrate S (e.g., drywall, cement board, etc.) in the tiled area using a thin adhesive A1 (this adhesive will be recognized by those skilled in the art). After sufficient drying / curing time (approximately 24 hours), tile T is adhered to the other side of membrane 10 using a thin adhesive A2. It will be understood that membrane 10 can be applied throughout corners, on irregular surfaces, and in non-linear locations (e.g., curved or wavy surfaces) where seams are not required.

[0030] In one embodiment, a method of establishing a waterproof barrier between a substrate and a tiled wall includes coating a waterproof membrane onto the substrate, the waterproof membrane having: a first nonwoven layer having first and second surfaces, a cross-laminated film layer, a second nonwoven layer having first and second surfaces, and adhesive layers located between the first nonwoven first surface and the cross-laminated film and between the second nonwoven first surface and the cross-laminated film. Tiles are then applied onto the waterproof membrane. The method may include applying a thin adhesive coating to the substrate, applying the waterproof membrane onto the thin adhesive, applying a second thin coating to the membrane, and applying the tiles onto the thin adhesive coating. The cross-laminated film may be an oriented cross-laminated film.

[0031] This membrane has been found to provide surprising flexibility and very light weight in high-strength structures. It is made from flexible films, such as VALERON. ® The strength and physical properties offered by the branded film allow for the use of significantly reduced polymer between nonwoven surface layers. This allows for thinner structures that are more flexible than known products. Furthermore, this provides a film that is easier to handle and apply to the work area. This is because the film layer can be a relatively thin element (approximately 3.0 mils) with reduced rigidity, making it easier to embed the product into a thin adhesive applied to the wall structure, and also allowing the film to adapt to corners, curved surfaces (such as arches), and surface irregularities. Due to its own weight, the lightweight nature of the film 10 helps prevent it from sliding down the wall during application.

[0032] Furthermore, the membrane provides an excellent barrier against water vapor. Oriented thin films, such as HDPE-based VALERON... ® The branded membrane provides an excellent barrier against water vapor, allowing its use in regular steam showers. Known lower-level barrier elements require thicker polymer layers to meet the requirements for use in steam showers. This results in thicker, less flexible, and heavier membranes.

[0033] A sample of the membrane according to this disclosure was compared with a sample of a commercially available waterproof membrane intended for use in areas likely to be exposed to high humidity. The sample was tested for: tensile breaking at pound per inch (lb / inch) in the machine direction and transverse direction according to ASTM D 882; tear propagation resistance (trouser tear) at pound per inch (lb / inch) in the machine direction and transverse direction according to ASTM D 1938; Toyo impact at kg*cm according to ASTM D 781 (mod); and water vapor transfer rate (WVTR) at US Perms (one grain of water vapor per hour, per square foot, per inch of mercury) at 37.8°C and 90% relative humidity according to ASTM E96-Program E. The basis weight of each sample was also measured. The results are shown in Table 1 below. Table 1 - This membrane and Commercially available waterproof membrane Comparison of various physical properties As can be seen from the data in Table 1 above, the membrane according to this disclosure has several advantages compared to commercially available waterproof membranes. This membrane is lighter and stronger in each of the tested categories. Furthermore, it exhibits a lower water vapor transmission rate when tested at 37.8°C and 90% relative humidity.

[0034] Adhesive layers or resins, such as elastomers used for laminating nonwoven materials and oriented cross-laminated film layers, provide excellent adhesion to HDPE-based films as well as PP or other oriented nonwoven materials. Again, the specific formulation of the adhesive layer can be varied to meet the requirements and applicability of adhesion between oriented cross-laminated films and nonwoven materials. Elastomer adhesive layers reduce the rigidity of the laminate, further enhancing the flexibility of the film.

[0035] In this disclosure, the words “a” or “an” will be understood to include both the singular and the plural. Conversely, any reference to a plural term should include the singular where appropriate.

[0036] As will be observed from the foregoing, many modifications and variations can be made without departing from the true spirit and scope of the novel concept of this membrane. It should be understood that this is not intended to, and should not be inferred to, be limiting with respect to the particular embodiments shown. This disclosure is intended to cover all such modifications falling within the scope of the appended claims.

Claims

1. A method for manufacturing a waterproof membrane, comprising the following steps: An HDPE cross-laminated film layer is adhered between first and second polypropylene nonwoven layers, each having a first and a second surface.

2. The method according to claim 1, wherein the cross-laminated film is an oriented cross-laminated film.

3. The method of claim 1, wherein the adhesion step is achieved by applying an adhesive layer between the first nonwoven layer and the cross-laminated film layer and by applying an adhesive layer between the second nonwoven layer and the cross-laminated film layer.

4. The method according to claim 3, wherein the method comprises the following steps: The first nonwoven layer is laminated to the cross-laminated film layer on one side, and the second nonwoven layer is laminated to the cross-laminated film layer on the side opposite to the cross-laminated film layer.

5. The method according to claim 4, wherein the lamination step is extrusion lamination.

6. A method for establishing a waterproof barrier between a substrate and a tiled wall, comprising: A waterproof membrane is coated on the substrate, the waterproof membrane having: a first nonwoven layer with first and second surfaces, a cross-laminated film layer, a second nonwoven layer with first and second surfaces, and an adhesive layer located between the first nonwoven first surface and the cross-laminated film and between the second nonwoven first surface and the cross-laminated film; as well as Tiles are applied onto the waterproof membrane.

7. The method according to claim 6, wherein the method comprises the following steps: A thin adhesive coating is applied to the substrate; The waterproof membrane is coated onto the thin adhesive, a second thin coating is applied onto the membrane, and the tile is applied onto the coating of the thin adhesive.

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