Building board with integral vapor-permeable water-resistant sheet membrane

Abstract

A building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, and a method for making the same, and a two-material layer laminate useful for making said building board, the building board comprising, in order, bonded together in face-to-face relationship, a WRB sheet, a polymeric bonding layer, and a board substrate, the polymeric bonding layer being comprised of a heat-activated or radio frequency activated fibrous web and having voids through the thickness of said layer such that the polymeric bonding layer has a water vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet, and the polymer of the polymeric bonding layer is at least equal to or greater than 1×10 at 20° C. 6 It has a modulus of elasticity (G') greater than Pa and a softening temperature greater than 122°F (50°C), the softening temperature being the temperature at which the polymer modulus of elasticity (G') drops to less than 30 percent of the polymer's modulus of elasticity (G') at 20°C, and the water vapor transmission rate through the building board is greater than or equal to 5 parms.

Description

[Technical field]

[0001] The present invention relates to materials for use in vapor-permeable water-resistant barriers (WRBs) and board substrates and panels for building construction. [Background technology]

[0002] Board substrates, such as typical 4×8 building panels, are used in the construction of the exterior of a building wall, with some board substrates attached to the wall studs using mechanical fasteners (nails, screws, etc.). Additionally, to improve the sealing of the building envelope and improve the energy performance of the wall, a vapor-permeable water-resistant barrier (WRB) sheet can be installed on the exterior of the wall as an air infiltration barrier, with this preformed sheet typically being mechanically fastened to the outer face of the board substrate. Applying the WRB sheet to the exterior of the wall after the wall has been constructed requires the additional step of first placing the WRB sheet on the wall surface and then attaching it to the wall.

[0003] Borenstein's US Patent Application Publication No. 2005 / 0214496 discloses a self-adhesive vapor-permeable air and moisture barrier sheet that can be installed on a building's structural surface without the use of mechanical fasteners. The vapor-permeable air and moisture barrier sheet is made self-adhesive by depositing an adhesive on one side of the sheet in a non-continuous film, leaving an area of ​​the membrane uncoated, which allows the diffusion of water vapor through the sheet in the uncoated area. A peelable release sheet or liner can then be deposited on the adhesive to allow the self-adhesive sheet to be packaged in a roll. In use, the release sheet or liner can be peeled off to expose the adhesive, which can then be adhered to a substrate. This type of "peel and stick" WRB sheet also has challenges when applied to building exteriors, including the tendency of the WRB sheet to stick to unwanted surfaces, such as itself, during installation. Peel and stick WRB sheets also have environmental and sustainability issues. The use of removable release sheets or liners creates significant waste because the discarded release sheet covers an area equal to the area of ​​the installed WRB sheet, and therefore the use of such WRB sheets results in an amount of paper waste equivalent to the entire building envelope. Summary of the Invention [Problem to be solved by the invention]

[0004] A building board with an integral WRB sheet would eliminate the need to apply the WRB sheet to the exterior of a building after the wall is erected. Thus, there is a need for a WRB sheet that can be packaged in a roll without a release liner, can be used without generating release liner waste, and has a polymeric bonding layer that can be integrated with the board substrate while continuing to function as a vapor-permeable water-resistant barrier. [Means for solving the problem]

[0005] The present invention relates to a method for providing a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, the method comprising: a) i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; and ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further comprising voids through the thickness of said layer such that the polymeric bonding layer has a water vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; The polymer in the polymeric bonding layer has a molecular weight of 1 × 10 at 20 °C. 6 providing a polymeric tie layer having a modulus (G') of greater than Pa and a softening temperature of greater than 122°F (50C), the softening temperature being the temperature at which the polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; b) laminating the WRB sheet and the polymeric tie layer face-to-face such that an inner sheet surface of the WRB sheet contacts an outer sheet surface of the polymeric tie layer; c) attaching the polymeric bonding layer to the WRB sheet by heat energy, radio frequency energy, pressure, or a combination thereof to form a two-material layer laminate; d) Furthermore, iii) providing a board substrate having an inner surface and an outer surface; e) laminating the two material layer laminate and a board substrate face-to-face with an inner sheet surface of the polymeric bonding layer in contact with an outer surface of the board substrate to form a non-integral building board; f) applying heat or radio frequency energy along with pressure to the non-integral building board to bond the two material layer laminate to a board substrate to form an integrated building board having an inner surface and an outer surface, the water vapor transmission rate through the building board being equal to or greater than 5 perms; Includes.

[0006] The present invention further relates to a method for making a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, the method comprising: a) i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; and ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer having a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard), the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further having voids through the thickness of said layer such that the polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; The polymer in the polymeric bonding layer has a molecular weight of 1 × 10 at 20 °C. 6 a polymeric tie layer having a modulus (G') of greater than Pa and a softening temperature of greater than 122°F (50C), the softening temperature being the temperature at which the polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; and iii) providing a board substrate having an inner surface and an outer surface; b) laminating i), ii), and iii) face to face such that an inner surface of the WRB sheet contacts an outer surface of the polymeric bonding layer and an inner surface of the polymeric bonding layer contacts an outer surface of the board substrate to form a non-integrated building board; and c) bonding the non-integrated building boards with heat or radio frequency energy in conjunction with pressure to form an integrated building board having an inner surface and an outer surface, the integrated building board having a water vapor transmission rate through the board of 5 palms or greater.

[0007] The present invention also provides a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, comprising: i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further comprising voids through the thickness of said layer such that the polymeric bonding layer has a water vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; The polymer in the polymeric bonding layer has a molecular weight of 1 × 10 at 20 °C. 6 a polymeric tie layer having a modulus (G') of greater than Pa and a softening temperature of greater than 122°F (50C), the softening temperature being the temperature at which the polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; iii) a board substrate having an inner surface and an outer surface; Including, i), ii), and iii), in turn, are joined together in an integrated building board; the WRB sheet is in face-to-face contact with the polymeric bonding layer, the inner surface of the WRB sheet being in contact with the outer surface of the polymeric bonding layer; the board substrate is in face-to-face contact with an inner surface of the polymeric bonding layer, the inner surface of the polymeric bonding layer being in contact with an outer surface of the board substrate; The water vapor transmission rate through the building board is greater than or equal to 5 parms. Regarding the building board.

[0008] The present invention still further relates to a two-material layer laminate suitable for use in making a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, the two-material layer laminate comprising: i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer having a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard), the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further having voids through the thickness of said layer such that the polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; The polymer in the polymeric bonding layer has a molecular weight of 1 × 10 at 20 °C. 6 a polymeric tie layer having a modulus (G') of greater than Pa and a softening temperature of greater than 122°F (50C), the softening temperature being the temperature at which the polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; The WRB sheet is secured face-to-face to the polymeric tie layer with the inner surface of the WRB sheet contacting the outer surface of the polymeric tie layer. [Brief description of the drawings]

[0009] [Figure 1] 1A and 1B are enlarged perspective and cross-sectional views, respectively, of a building board having an integral WRB sheet, the WRB sheet, a polymeric bonding layer of one or more heat-activated or radio frequency activated fibrous webs, and a board substrate, the views not being drawn to scale. [Diagram 2] 1A and 1B are enlarged perspective and cross-sectional views, respectively, of a building board having an integral WRB sheet, the WRB sheet, a polymeric bonding layer of one or more heat-activated or radio frequency activated fibrous webs, and a board substrate, the views not being drawn to scale. [Diagram 3] 1 is a photograph of a screw fastener that has been overdriven into the face of a building board having an integral WRB sheet. [Figure 4]Photograph of a building board with integral WRB sheet further having passing water holdout performance after testing, where the screw fasteners have been removed and the board cut along the centerline of the screw fastener holes, showing that no water damage to the board has occurred. [Diagram 5] Photograph of a building board with an integral WRB sheet that did not have passing water retention performance because the screw fasteners were driven too deeply into the building board, with the screw fasteners removed and the board cut along the centerline of the screw fastener holes to show the dark areas where extensive water damage occurred. [Figure 6] 1 is a graph showing the relationship between basis weight of a polymeric bonding layer comprised of one or more heat-activated or radio frequency activated fibrous webs and water vapor transport through a building board having an integral WRB sheet. [Figure 7] 1 is a photograph showing the appearance of various weights of polymeric bonding layers in a building board after a heat-activated or radio frequency activated fibrous web has been integrated with a WRB and a board substrate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The inventors have discovered that a building board with an integral WRB sheet eliminates the need to apply the WRB sheet to the exterior of a building after the wall is erected. A polymeric bonding layer can be attached to the WRB sheet to form a two-material layer laminate that can be made and stored in roll form without the need for an additional release liner to protect the polymeric bonding layer from adhering to itself or other layers until desired. The two-material layer laminate can further be integrated with the board substrate while still functioning as a vapor-permeable water-resistant barrier without generating any release liner waste.

[0011] Building board with integral WRB sheet A building board with an integral WRB sheet, in order, comprises a WRB sheet, a polymeric bonding layer, and a board substrate, all bonded together in a face-to-face manner. The polymeric bonding layer comprises one or more heat-activated or radio-frequency activated fibrous webs. All fibrous webs have web-like voids, and the polymeric bonding layer has voids throughout its thickness, so that the polymeric bonding layer can have a water vapor transmission rate through the layer equal to or greater than that of the WRB sheet. The voids are maintained in place after the WRB sheet, the polymeric bonding layer, and the board substrate are all bonded together. This results in a water vapor transmission rate through the building board of 5 perms or greater.

[0012] The polymeric bonding layer of the heat-activated or radio-frequency-activated fiber web has a thermal adhesion of 1×10 at 20°C. 6 The polymeric bonding layer is made from a polymer having a modulus (G') of greater than 1×10 Pa and a softening temperature of greater than 122° F. (50° C.), the softening temperature being the temperature at which the modulus (G') of the polymer drops to less than 30% of the modulus (G') of the polymer at 20° C. In some preferred embodiments, the heat-activated or radio-frequency-activated fibrous web of the polymeric bonding layer has a modulus of elasticity of less than 1×10 at 20° C. 7 It is made from a polymer that has a modulus of elasticity (G') greater than Pa and a softening temperature greater than 122° F. (50° C.), the softening temperature being the temperature at which the modulus of elasticity (G') of the polymer drops to less than 30% of the modulus of elasticity (G') of the polymer at 20° C. These properties ensure that the polymeric bonding layer is non-tacky and non-blocking, and the two material layer laminate can be packaged in a roll and used without a release liner.

[0013] Non-tacky means that a layer will not adhere to itself by mere surface contact of one layer with another. Blocking is a term used to describe the tendency of some polymer sheets, when formed into rolls or placed in a stack, to adhere to each other over time and form "blocks" of laminated polymer even at room temperature, even though, as adhesives they are typically used, the polymer sheets are heated to high temperatures and pressure is applied to make them adhesive. Non-blocking means that the polymeric bonding layer is not only non-tacky, but also remains unadhered to other surfaces under pressure and at normal ambient temperature ranges (specifically ISO 11502, Method A) and remains unadhered until the polymeric bonding layer is activated by application of heat or radio frequency energy.

[0014] The phrases "building board having an integral WRB sheet" and "integrated building board" are used interchangeably herein. The phrase "board substrate" refers to a substrate that is modified to create a building board having an integral WRB sheet. Figure 1 is an enlarged perspective view, not drawn to scale, and Figure 2 is a cross-sectional view, of an integrated building board 1 consisting of a WRB sheet 2, a polymeric bonding layer 3 consisting of a heat-activated or radio frequency activated fibrous web, and a board substrate 4.

[0015] Thus, in one embodiment, a building board having an integral WRB sheet is i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further having voids through the thickness of said layer such that the polymeric bonding layer has a water vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; iii) a board substrate having an inner surface and an outer surface; Including, i), ii), and iii), in order, are joined together in an integrated building board, the WRB sheet facing the polymeric bonding layer, the inner surface of the WRB sheet being in contact with the outer surface of the polymeric bonding layer, and the board substrate facing the inner surface of the polymeric bonding layer, the inner surface of the polymeric bonding layer being in contact with the outer surface of the board substrate; The water vapor transmission rate through the building board is greater than or equal to 5 parms.

[0016] This level of moisture vapor transmission through the building board (5 palms or greater) ensures that the building board meets most building codes. In some embodiments, a building board with an integral WRB sheet has a moisture vapor transmission through the building board of 10 palms or greater.

[0017] The faces of a building board having an integral WRB sheet generally have the same shape as the faces of the board substrate, polymeric bonding layer, and WRB sheet, which can be any common shape (e.g., rectangular, triangular, circular, etc.), although it is preferred that all faces are rectangular (including square), which is the most preferred overall shape for boards used in general building construction.

[0018] Board Base Material The building board with the integral WRB sheet can include any board substrate suitable for use on exterior walls as a wall covering. Such board substrates are often made of wood, such as plywood, oriented strand board (OSB), or particle board. In addition, other suitable boards include boards made of gypsum and magnesium oxide, boards that are themselves composite materials made of wood fiber, continuous insulation, Thermoply™, fiberglass, and fire-retardant treated wood, as well as boards made of metal, lightweight concrete, laminated timber, and structural glass. The boards can be further covered with a fibrous covering, such as paper, aluminum cladding, or fiberglass mat. In some embodiments, the board substrate is gypsum board, and in still other embodiments, the board substrate is gypsum board further covered on both major sides with fiberglass mat, such as DensGlass® Sheathing, a gypsum panel with a fiberglass mat surface treatment available from Georgia Pacific Gypsum.

[0019] A board substrate typically has two faces that form a plane and four small edges that form the boundaries of that plane. For example, in a typical 4' x 8' piece of 1 / 2" plywood, each face has the dimensions 4' x 8', but is slightly less than 1 / 2" thick. When used in walls, a board substrate typically has an inner face that is the face closest to the interior of the building, and an outer face that is typically the face closest to the exterior of the building.

[0020] Water Resistant Barrier (WRB) Sheet The water-resistant barrier (WRB) sheet has a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours as measured by the LYSSY method. In some other embodiments, the WRB sheet is substantially liquid impermeable, preferably has a hydrostatic head of at least 130 grams per square meter per 24 hours, is substantially air impermeable, and preferably has a Gurley Hill porosity of 300 seconds or more. In some other embodiments, the WRB sheet is preferably has a water vapor transmission rate of at least 370 grams per square meter per 24 hours.

[0021] In some embodiments, the WRB sheet has a basis weight range of 50 to 100 grams per square meter. Basis weights below about 50 grams per square meter are likely to be too weak for construction uses, and basis weights above 100 grams per square meter are considered undesirable as the additional weight does not provide any appreciable mechanical advantage.

[0022] Preferred WRB sheeting meets the requirements of building codes such as ASTM E2556, Standard Specification for a WRB, which requires a dry tensile strength (in both the machine and cross directions (MD / CD)) of at least 20 pounds per inch per ASTM D828, and water resistance (held at 55 cm) of no leak for 5 hours per AATCC 127.

[0023] In some embodiments, the WRB sheet has a hydrostatic head in the range of 55-1500 cm of water. A WRB sheet with a hydrostatic head less than 55 cm is considered to be too porous to liquids, and a WRB sheet with a hydrostatic head greater than 1500 cm generally requires additional sheet weight that may not be needed. In some embodiments, the WRB sheet has a hydrostatic head in the range of 180-1000 cm of water, with a hydrostatic head in the range of 200-500 cm of water being particularly preferred.

[0024] In some embodiments, the Gurley Hill porosity of the WRB sheet ranges from 250 seconds to 6000 seconds. WRB sheets with a Gurley Hill porosity of less than 250 seconds are considered to be too porous to allow air to pass through, and WRB sheets with a Gurley Hill porosity of more than 6000 seconds are generally considered to require additional sheet weight that is not particularly considered necessary for construction uses. In some embodiments, the Gurley Hill porosity of the WRB sheet ranges from 250 seconds to 6000 seconds, with Gurley Hill porosities in the range of 300 seconds to 5000 seconds being particularly preferred.

[0025] In some embodiments, the WRB sheet has a "wet cup" LYSSY water vapor transmission rate in the range of 40 to 2000 grams per square meter per 24 hours. It is believed that a measured water vapor transmission rate below 40 grams per square meter per 24 hours may result in excess liquid water forming on the surface of the WRB sheet, but a water vapor transmission rate of greater than 2000 grams per square meter per 24 hours is sufficient for even the most humid situations. In some embodiments, a water vapor transmission rate of greater than 250 grams per square meter per 24 hours is desirable. Similarly, in some embodiments, a water vapor transmission rate in the range of 65 to 1870 grams per square meter per 24 hours is desirable, and in other embodiments, a water vapor transmission rate in the range of 130 to 1870 grams per square meter per 24 hours is desirable. Preferably, in some embodiments, the WRB sheet meets a "dry-cup" water vapor transmission rate of at least 5 palms per ASTM E96 / E96M.

[0026] Useful WRB sheets are generally any sheet material that does not permit or restrict the movement of liquid water through the sheet, but does permit some movement of vapor, particularly water vapor, through the sheet. In some embodiments, the WRB sheet is polymeric. Preferred polymeric sheets are polyethylene (PE) or polypropylene (PP). One preferred WRB sheet is a nonwoven fibrous web of flash-spun plexifilamentary high density PE (HDPE) fibers sold under the trade name Tyvek® Homewrap™ or Tyvek® CommercialWrap by DuPont, Wilmington, DE. A suitable polypropylene substrate is available under the trade name Typar® Building Wraps.

[0027] The water-resistant barrier sheet is preferably coextensive with and completely covers the exterior surface of the board substrate of a building board having an integral WRB sheet.

[0028] Polymer Binder Layer The polymeric bonding layer has an inner sheet surface and an outer sheet surface, and the polymeric bonding layer comprises one or more heat-activated or radio-frequency activated fibrous webs. By heat-activated or radio-frequency activated fibrous webs is meant a polymeric fibrous web that can be at least partially melted by application of thermal energy, such as by application of heat by direct contact or in an oven, or by application of radio-frequency energy, such as by application of an electromagnetic field as used in radio-frequency welding devices, or by application of ultrasonic energy, such as used in ultrasonic bonding devices. As used herein, radio-frequency energy is intended to include ultrasonic energy.

[0029] The phrase "polymeric bonding layer" as used herein also means "polymeric bonding layer material layer", meaning that the polymeric bonding layer can include multiple heat-activated or radio-frequency activated fibrous webs. These fibrous webs can have very low basis weights, so multiple lamina of these fibrous webs can be combined and used together as the polymeric bonding layer or as the polymeric bonding material layer. One preferred embodiment of the polymeric bonding layer uses multiple lamina of fibrous webs, all of which are the same fibrous web and made from the same polymer.

[0030] Suitable heat-activated or radio-frequency activated fibrous webs include nonwoven fibrous webs made from linear or branched thermoplastic hydrocarbon polymers such as polyolefins (particularly polyethylene and polypropylene), polyesters, polyurethanes, and other thermoplastic polymers such as polyamides, as well as mixtures and copolymers of any of these. Preferably, the heat-activated or radio-frequency activated fibrous web is a nonwoven fibrous web made from a polyolefin polymer or copolymer.

[0031] The polymeric bonding layer of the heat-activated or radio-frequency-activated fiber web has a thermal adhesion of 1×10 at 20°C. 6 The fibrous web is made from a polymer having a modulus of elasticity (G') greater than Pa and a softening temperature greater than 122°F (50°C). It is understood that the polymer in the heat-activated or radio-frequency activated fibrous web must be softened by exposing the web to heat energy or by radio-frequency energy to reach a temperature of 60-150°C. Preferably, the heat-activated or radio-frequency activated fibrous web must be softened by exposing the web to heat energy or by radio-frequency energy to reach a temperature of 90-120°C.

[0032] In some embodiments, the polymers used in the heat or radio frequency activated fibrous webs further have a melting point of 60-150° C., preferably 80-120° C. In other embodiments, the polymers used in the heat or radio frequency activated fibrous webs have a melting point of 100° C. (230° F.) or less.

[0033] The polymeric bonding layer, as well as the heat-activated or radio frequency activated fibrous web which forms the polymeric bonding layer, have voids throughout their thickness such that the polymeric bonding layer and the heat-activated or radio frequency activated fibrous web have a water vapor transmission rate through the layer at least equal to or greater than that of the WRB sheet to avoid the polymeric bonding layer being an unacceptable barrier to the passage of water vapor through the final building board having the integral WRB sheet, which is important in that the final integrated building board will have a water vapor transmission rate of 5 palms or greater.

[0034] 6 is a graph showing the relationship between basis weight of a polymeric bonding layer comprised of one or more heat- or radio frequency-activated fibrous webs and water vapor transport through a building board having an integral WRB sheet, as evaluated using ASTM E96 Method B. As shown, as the basis weight of the heat- or radio frequency-activated fibrous web decreases, the amount of water vapor that can pass through the integrated building board increases.

[0035] It is believed to be important that the fibrous web-like properties of the heat-activated or radio-frequency activated fibrous web are substantially retained after the heat-activated or radio-frequency activated fibrous web is integrated into the polymeric bonding layer in the integrated building board. To simulate the appearance of the polymeric bonding layer in the integrated building board, a non-integrated simulated building board was made by stacking the heat-activated or radio-frequency activated fibrous web onto a gypsum substrate board with an outer sheath of glass fiber mat. In addition, no WRB sheets were stacked on the heat-activated or radio-frequency activated fibrous web, but instead a release paper liner was used. The non-integrated simulated building board was then placed into a Carver hydraulic press with metal platens heated to 120° C. and pressed with 2000 pounds of force for 60 seconds. The integrated simulated building board was then removed from the press, cooled, and the release paper liner was removed. The resulting polymeric bonding layer was visible on the surface of the gypsum substrate board. To better visualize and confirm that the polymeric bonding layer maintained the properties of the fiber web and the voids between the strands of the bonded fiber web, a black sealant was applied to the surface of the integrated simulated building board, and then a metal spatula was used as a doctor blade to remove all excess black material from the surface of the polymeric bonding layer of the bonded fiber web, while retaining the black material in the voids between the strands of the bonded fiber web. Figure 7 shows photos of the appearance of the various weights of polymeric bonding layers used in this simulation, which is the same as the expected structure after the heat-activated or radio-frequency-activated fiber web is integrated with the WRB sheet and board substrate. The integrated simulated building board was made of 10 g / m 2 (0.3 oz / yd 2 ) heat-activated or radio-frequency activated fibrous web. 2 (0.3 oz / yd 2 ) fiber web layers, totaling 20.3 g / m 2 (0.6 oz / yd 2 ) the first region 20, 10 g / m 2 (0.3 oz / yd 2 ) fiber web layers, totaling 40.7 g / m 2(1.2 oz / yd 2 ) in the second region 21, 10 g / m 2 (0.3 oz / yd 2 ) fiber web layers, totaling 61.0 g / m 2 (1.8 oz / yd 2 ), and a control area 23 having no heat or radio frequency activated fibrous web.

[0036] Thus, the above simulations indicate that the desired open fibrous web structure can be maintained in the integrated building board. The total basis weight of the polymeric bonding layer is about 17-70 grams per square meter (0.5-2 ounces per square yard). In addition, the estimated open area, or void area, of the polymeric bonding layer is shown in Table 1.

[0037] [Table 1]

[0038] In some embodiments, the heat activated or radio frequency activated fibrous web has a basis weight of 34 grams per square meter (1.0 ounce per square yard) or less, which provides an open area between the surface of the WRB sheet and the surface of the building board of about 50%.

[0039] Sealing against overdriven fasteners Surprisingly, it has been found that the addition of a polymeric bonding layer consisting of a heat-activated or radio frequency activated fibrous web interposed between and bonded to the surface of the WRB sheet and the surface of the board can dramatically reduce the risk of WRB sheet failure due to certain overdriven fasteners during installation of the integrated building board. The use of a fibrous web structure as the polymeric bonding layer further allows sufficient water vapor to pass through the wall and also prevents lateral movement of air and water between the surface of the WRB sheet and the surface of the board.

[0040] The concept of over-driven fasteners is illustrated in Figure 3, which is a photograph of a screw fastener that has been over-driven into the surface of an integrated building board, and as shown, the exterior surface of the WRB sheet 10 is shown sagging and stretched into the surface of the board by the head of the Phillips head screw fastener 11 embedded in the board, i.e., the top surface of the Phillips head screw fastener 11 is driven a linear distance below the exterior surface of the board, rather than being flush with the exterior surface of the WRB sheet at the exterior surface of the board. Again, as shown, the shoulder of the WRB sheet formed by the head of the screw is smooth and not fractured, and the liquid barrier performance function of the WRB sheet is likely not compromised by this over-driven fastener.

[0041] As used herein, the term "over-driven" means that the top surface of the fastener is not flush with the outer surface of the WRB sheet on the outer surface of the board, but is driven into the board a linear distance below the outer building board surface. The term "fastener" is intended to include such things as screws, nails, staples, and other mechanical devices used to attach an integrated building board in a wall. In some embodiments, the preferred fastener is a screw. The techniques used herein are expected to provide improved sealing performance for fasteners that are over-driven into the building board a linear distance below its outer surface by as much as 0.03 inches, and preferably exhibit improved sealing performance for fasteners that are over-driven into the building board a linear distance below its outer surface by as much as 0.04 inches, or even greater linear distances.

[0042] Figures 4 and 5 show the effects of sealing and leakage that can occur from overdriven fasteners. Figure 4 is a photograph of an integrated building board with passing water retention performance after testing under a specified head of liquid water as described in modified ASTM method D1970-15 as specified in the test method herein. The integrated building board includes a gypsum board substrate 15 and a WRB sheet 12, bonded together with a polymeric bonding layer 14 inserted therebetween. The integrated building board was tested for water leakage at overdriven screw fasteners that were overdriven from the exterior surface to 0.045 into the integrated building board. After testing, the screw fasteners were removed and the integrated building board was cut from the centerline of the screw fastener holes to reveal if water had penetrated under the WRB sheet. As shown in Figure 4, the integrated building board shows no water damage.

[0043] In contrast, Figure 5 is a photograph of an integrated building board that failed water retention performance after testing. Similar to Figure 4, the integrated building board was water leak tested with over-driven screw fasteners, but in this example, the screw fasteners were over-driven into the integrated building board by 0.06 inches from the exterior surface. Again, after testing, the screw fasteners were removed and the integrated building board was cut from the centerline of the screw fastener holes to reveal water damaged (darkened) areas 16 in the gypsum board surrounding the holes. Thus, Figure 5 is an illustration of failed seal performance.

[0044] It is believed that the polymeric bonding layer provides a cushioning effect to the WRB sheet when the fastener is driven into the integrated building board, i.e., the polymeric bonding layer allows the WRB sheet to deform in the plane of the building board rather than tearing at the surface of the building board. Thus, in some embodiments, the heat-activated or radio-frequency activated fibrous web used in the polymeric bonding layer can have a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard). 2 (0.5 oz / yd 2) is believed not to provide sufficient cushioning to the board, while a basis weight of 70 g / m 2 (2 oz / yd 2 ) basis weights are not only uneconomical but also begin to affect water vapor transport through the board.

[0045] Method for making building boards with integral WRB sheets In one embodiment, the present invention relates to a method for providing a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, the method comprising: a) i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; and ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further comprising voids through the thickness of said layer such that the polymeric bonding layer has a water vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet. Providing b) laminating the WRB sheet and the polymeric tie layer face-to-face such that an inner surface of the WRB sheet contacts an outer surface of the polymeric tie layer; c) attaching the polymeric bonding layer to the WRB sheet by heat energy, radio frequency energy, pressure, or a combination thereof to form a two-material layer laminate; d) Furthermore, iii) providing a board substrate having an inner surface and an outer surface; e) laminating the two material layer laminate and a board substrate face-to-face with an inner surface of the polymeric bonding layer in contact with an outer surface of the board substrate to form a non-integral building board; f) applying heat or radio frequency energy along with pressure to the non-integral building board to bond the two material layer laminate to a board substrate to form an integrated building board having an inner surface and an outer surface, the board having a water vapor transmission rate of 5 palms or greater; Includes.

[0046] Step b) of laminating the WRB sheet and the polymeric bonding layer face to face, and step c) of fastening the polymeric bonding layer to the WRB sheet to form a two-material layer laminate, can be performed in either a batch, semi-continuous, or continuous process. For example, in a batch process, the WRB sheet can be overlaid with the polymeric bonding layer, and then the two-material stack can be placed in a platen press, where only one platen is heated, and the WRB sheet can be applied to the heated platen to fasten the polymeric bonding layer to the WRB sheet. The press is closed, and heating can be very brief, i.e., a few seconds, and is only necessary to raise the surface of the polymeric bonding layer at the interface of the WRB sheet so that it can be fastened to the WRB sheet. The temperature of the heated platen depends on the type of polymer used in the polymeric bonding layer and the desired residence time in the press. In addition, the temperature of the heated platen must not be such that the WRB sheet is damaged.

[0047] Similarly, in a batch process, steps e) and f) of consolidating the two-material layer laminate and board substrate into a building board with an integral WRB sheet can be accomplished in a similar manner by overlaying the two-material layer laminate on a substrate board, contacting the polymeric bonding layer to the substrate board, and consolidating the combination of substrate board and two-material layer laminate between two heated platens in a press. Again, the temperature of the heated platens will vary depending on the type of polymer used in the polymeric bonding layer, the desired residence time in the press, and the type of WRB sheet, but typically the temperature of the platens should be 90° C. or higher. It is believed that typical processing ranges for consolidating the layers via a batch process include a temperature range of about 90° C. to about 200° C., and a pressure range of about 50 to about 300 KPa, with a residence time in the press of about 2 seconds to about 60 seconds. It is believed that these conditions are suitable for consolidating the two-material layer laminate and board substrate into a building board with an integral WRB sheet that maintains voids in the polymeric bonding layer.

[0048] Continuous and semi-continuous processes typically use a WRB sheet provided in a roll, and if the polymeric bonding layer is also provided in a roll, the two materials can be laminated together using two or more rewinds that place and combine the sheets together in a continuous process. The advantage of this process is that the laminated sheets can then be fastened together and wound into a roll, and the roll of two-material layer laminate can be packaged and stored. The roll of two-material layer laminate can then be used in a subsequent step to form a building board with an integral WRB sheet, or can be stored for later use.

[0049] Methods of fastening the polymer layer to the WRB sheet include point bonding using a calendar roll, patterned ultrasonic bonding, continuous conveyor, and other methods that can provide a small amount of energy to enhance the surface of the polymeric bonding layer at the interface of the WRB sheet so that it can be fastened to the WRB sheet. As used herein, a fastening process is considered to apply only as much energy to the polymeric bonding layer as would activate the surface filaments of a heat-activated or radio-frequency activated fibrous web. This allows the two sheets to be locally bonded together as much as is necessary to allow the two-material layer laminate to be used as a single sheet. When any form of point bonding or pattern bonding is used to fasten the layers together, the two layers are considered to be fastened together if no more than 50 percent of the total surface area of ​​the WRB sheet surface is connected to the sheet surface of the polymeric bonding layer. In some instances, no more than 20 percent of the total surface area of ​​the WRB sheet surface is connected to the sheet surface of the polymeric bonding layer sheet. Preferably, no more than 10 percent of the total surface area of ​​the WRB sheet face is connected to the sheet face of the polymeric tie layer sheet, and most preferably, no more than 5 percent of the total surface area of ​​the WRB sheet face is connected to the sheet face of the polymeric tie layer sheet.

[0050] Alternatively, the polymer layer and the WRB sheet can be fastened together using a conveyor arrangement or belt press. For example, the combination of the WRB sheet and the polymer bonding layer can be advanced between two conveyors, one of which is heated and the other of which is unheated or cooled. The combination of the WRB sheet and the polymer bonding layer is placed with the WRB sheet facing the heated conveyor and the polymer bonding layer facing the unheated or cooled conveyor. Sufficient heat penetrates the WRB sheet from the heated conveyor to reach the interface between the two materials, activating the surface filaments of the polymer bonding layer and fastening the layer to the WRB sheet. Furthermore, it is believed that the use of multiple heat-activated or radio-frequency activated fibrous webs in the polymer bonding layer allows for sufficient web-like voids to exist between the webs such that some of the surface filaments of each web are activated to fasten all the webs and the WRB sheet together. Again, the temperature and pressure profile between the two conveyors depends on the polymer in the bonding layer, the WRB sheet, and the advancement speed (residence time) in the heated zone.

[0051] Similarly, the process of forming a two-material layer laminate can be accomplished by placing an individually cut sheet of heat-activated or radio frequency activated fibrous web (which constitutes the polymeric bonding layer) onto a continuous WRB sheet that is indexed after placing the cut sheet of the polymeric bonding layer. Again, the two materials can be further fastened by indexing via a roll, or press, or transport system that lightly fastens one sheet to the other, section by section.

[0052] Any of these roll, conveyor, press, or contact processes used to fasten the layers of the two-material laminate together can completely melt the web at selective locations to fasten the polymeric tie layer to the WRB sheet and bond the polymeric tie layer to the WRB sheet. The total surface area of ​​the bond between the polymeric tie layer sheet surface and the WRB sheet surface created by melting the polymeric tie layer in this manner is, in some embodiments, 50 percent or less of the total surface area of ​​the WRB sheet surface connected to the polymeric tie layer sheet surface. In some examples, the bond between the polymeric tie layer sheet surface and the WRB sheet surface created by melting the polymeric tie layer in this manner is preferably 20 percent or less of the total surface area of ​​the WRB sheet surface connected to the polymeric tie layer sheet surface. In some examples, the adhesion between the polymer bonding layer sheet surface and the WRB sheet surface created by melting the polymer bonding layer in this manner is more preferably 10 percent or less of the total surface area of ​​the WRB sheet surface connected to the polymer bonding layer sheet surface, and in still other examples, the adhesion between the polymer bonding layer sheet surface and the WRB sheet surface created by melting the polymer bonding layer in this manner is most preferably 5 percent or less of the total surface area of ​​the WRB sheet surface connected to the polymer bonding layer sheet surface.

[0053] Similarly, e) laminating the two-material layer laminate and the board substrate face-to-face to form a non-integrated building board, and f) bonding the non-integrated building board to form an integrated building board with an integral WRB sheet, can be accomplished in a manner similar to the formation of a conventional two-material laminate WRB sheet-polymer bonded layer laminate, but using the two-material layer laminate and the substrate board as two layers as well. If the two-material layer laminate is in roll form, the two-material layer laminate can be unwound onto a moving conveyor of board substrate to form a non-integrated building board, and then bonded and consolidated using a belt press or a series of calendar rolls to form an integrated building board. Alternatively, a process can be used in which the two-material layer laminate and the board substrate are combined using an index combination to form a non-integrated building board, and then bonded and consolidated using pressure and heat and / or radio frequency energy.

[0054] In yet another process, it is believed that the polymeric bonding layer and WRB sheet can be applied to the board substrate immediately after its manufacture, provided that the substrate retains sufficient heat to activate the polymeric bonding layer. Alternatively, it is believed that a similar result can be achieved by first heating the substrate and then applying the polymeric bonding layer and WRB sheet. If desired, additional pressure can be applied to the combined materials in either process after the polymeric bonding layer / WRB sheet combination is applied to the heated substrate.

[0055] There are many different process series possibilities for consolidating non-integrated building boards into building boards with integral WRB sheets. The exact applied energy and pressure conditions for each process series will depend on many variables, such as the type of equipment and desired production rate, as well as the type and amount of WRB sheet, polymeric tie layer, and board substrate, but it is believed that such conditions can be determined using the batch process conditions previously described herein as a general guide to the conditions.

[0056] Using sufficient heat (and / or energy) and any necessary pressure to make a building board with an integral WRB sheet, the two-material layer laminate can be bonded together to a board substrate board using any of the roll, conveyor, press, or contact processes described hereinabove to make a building board with an integral WRB sheet, or the individual material layers of the WRB sheet, polymeric bonding layer, and board substrate can be bonded together to make a building board with an integral WRB sheet. It is believed that the combination of the light basis weight of the polymeric bonding layer and its web-like voids limits the spread of the molten web on the surface of the board substrate, so that even if the entire web melts, it does not spread enough to form a continuous blocking film on the surface of the board (see Reference Example 1). It is believed that this allows the entire non-integrated board to be consolidated over a wide range of conditions, and the bonding conditions of the board are only slightly limited to the extent that the WRB sheet must not be damaged.

[0057] In some embodiments, a WRB sheet is considered to be integral to an integrated building board if the WRB sheet is attached to a board substrate via a polymeric bonding layer such that the force to peel the WRB sheet from the board substrate is at least 0.2 pounds per linear inch as determined by ASTM D3330 F-04. Otherwise, the combination of the WRB sheet, polymeric bonding layer, and board substrate is not considered to be sufficiently integrated together to be practically used as a single piece in some applications.

[0058] It is further understood that selected features and elements described herein above can be used in a more straightforward manner to make a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet. For example, in some embodiments, the present invention relates to a method for making a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, the method comprising: a) i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; and ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer having a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard), the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further having voids through the thickness of said layer such that the polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; and iii) a board substrate having an inner surface and an outer surface Providing b) laminating i), ii), and iii) face to face such that an inner surface of the WRB sheet contacts an outer surface of the polymeric bonding layer and an inner surface of the polymeric bonding layer contacts an outer surface of the board substrate to form a non-integrated building board; c) bonding the non-integral building boards with heat or radio frequency energy in conjunction with pressure to form an integrated building board having an inner surface and an outer surface, the integrated building board having a water vapor transmission rate through the board of at least 5 perms; Includes.

[0059] As can be readily seen, this process provides a more direct way to achieve a building board with an integral vapor-permeable water-resistant barrier (WRB) sheet since a two-material layer laminate is not first formed. It is understood and intended that the features, elements, and principles disclosed herein for attaching a two-material layer laminate to a substrate board using batch, semi-continuous, continuous, and other processes can also all be applied and used in this direct process with little or no modification. To avoid repetition, they will not be repeated here.

[0060] Two-layer laminate It is believed that the two-material layer laminate including the WRB sheet and the polymeric bonding layer can be combined in many different ways with a variety of boards and panels. Thus, in yet another embodiment, the present invention relates to a two-material layer laminate suitable for use in making a building board having an integral WRB sheet, the two-material layer laminate comprising: i) a WRB sheet having an inner surface and an outer surface, the WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a water vapor transmission rate of at least 40 grams per square meter per 24 hours; ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, the polymeric bonding layer having a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard), the polymeric bonding layer being comprised of a heat activated or radio frequency activated fibrous web, the polymeric bonding layer further having voids through the thickness of said layer such that the polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of the WRB sheet; Including, The WRB sheet is secured face-to-face to the polymeric tie layer with the inner surface of the WRB sheet contacting the outer surface of the polymeric tie layer.

[0061] The two-material layer laminate can be made by the methods previously described herein and can be used in the methods previously described herein, where the two-ply WRB sheet / polymeric bonding layer laminate is combined with a board substrate and then bonded to the board with heat (and / or energy) and any necessary pressure to make a building board having an integral WRB sheet. However, if desired, it is contemplated that the two-material layer laminate can also be used in the field and attached to a wall with sufficient labor to place the polymeric bonding layer between the WRB sheet and the wall surface. Local bonding to the wall surface can be done manually with heated rollers, heating blocks, or other equipment.

[0062] Test Method Fastener Sealability. The ability of the WRB sheet to seal around fasteners was determined according to a modified ASTM method D1970-15. ASTM D1970-15 was modified as follows: The fasteners were 4.13 cm long self-drill Phillips Head drywall screws (#6). The WRB sheets were tested on 4 in. x 4 in. (10.2 cm x 10.2 cm) square gypsum board specimens that were 1.3 cm thick and had a wooden backing. For each WRB sheet test, one screw was driven into the center and into the wooden backing of each of four separate square gypsum board specimens covered with the WRB sheet. No spacers were used on the outside of the installed WRB sheet. Further differences from ASTM Dl970-15 were that the fastener heads were overdriven into the board specimens to various depths rather than flush with the outer surface of the board specimens, and the 3-day test period was conducted in a laboratory maintained at 23°C (75°F and 50% relative humidity) rather than in a refrigerated room at 5°C. The pass criterion for passing the fastener seal test was that no visible water was found under the WRB sheet for each specimen. If all four replicate specimens had no visible water found under the WRB sheet, the WRB sheet was considered to have passed the test. If even one of the four specimens did not pass, the WRB sheet was considered to have failed. EXAMPLES

[0063] Example 1 This example illustrates one method of making a two-material layer laminate including a WRB sheet and a polymeric tie layer.

[0064] The WRB sheet is Tyvek® Commercial Wrap, 92 g / m 2 (2.7 osy) basis weight, 280 cm hydrostatic head, Gurley Hill porosity greater than 1500 seconds, and 163 g / m per 24 hours. 2 The polyethylene sheet material is a flash spun polyethylene sheet material having a moisture vapor transmission rate (ASTM E96, Method A) of 0.01 to 0.01%.

[0065] The polymeric bonding layer is 10 g / m 2 The non-tacky POF4002 heat activated fibrous web was obtained from Spunfab with a basis weight of 0.3 osy. The polymer in the polymeric bonding layer was measured to have a modulus of elasticity (G') of 20 MPa (19.6 x 10 6 The compressive strength (MPa) and softening temperature were 95°C.

[0066] A two-material layer laminate including a WRB sheet and a polymeric bonding layer is made by cutting the WRB sheet and the polymeric bonding layer into squares of the same size, then overlapping the WRB sheet square with a square of the polymeric bonding layer, so that the face of the polymeric bonding layer sample is in face contact with the face of the WRB sheet sample. Depending on the basis weight of the individual polymeric bonding layers, multiple layers of the polymeric bonding layer are overlapped on the WRB sheet to make up the desired polymeric bonding layer basis weight, each of which is also in face contact with each other. For example, a 10 g / m 2 (0.3osy) fiber webs are used, resulting in a 20g / m 2 A polymeric bonding layer having a basis weight of 0.6 osy is obtained. The four edges of the sheet are then aligned so that the edges of the polymeric bonding layer and the edges of the WRB sheet sample are coextensive with one another. The polymeric bonding layer is then secured to the WRB sheet by contacting a face of the WRB sheet (the outer surface opposite the polymeric bonding layer) to a single heated platen and briefly heating the combined layers in contact in a press with only one side of the press heated. Heat is conducted through the WRB sheet to the interface with the polymeric bonding layer, melting some of the surface filaments and securing all of the layers together. The total basis weight of the resulting two-material layer laminate using two sheets of polymeric bonding layer is about 112 g / m 2 (3.3osy).

[0067] The resulting laminate samples are easy to handle and roll up and do not further adhere to other materials until additional energy is applied to the laminate to activate the polymeric tie layer.

[0068] Example 2 This example shows one way to make a building board with an integral WRB sheet using the two-material layer laminate of Example 1. DensGlass® Sheathing, a gypsum panel with a fiberglass mat finish available from Georgia Pacific Gypsum, is cut into a 4 inch by 4 inch (10.2 cm by 10.2 cm) square gypsum board sample. Similarly, a 4 inch by 4 inch (10.2 cm by 10.2 cm) square sample of a two-material layer laminate including the WRB sheet of Example 1 and a polymeric bonding layer is also made. The square of the two-material layer laminate is then placed in a stack on top of the square of gypsum board, with the face of the polymeric bonding layer in face-to-face contact with the face of the gypsum board. The four edges of the two-material layer laminate and the gypsum board are then aligned so that they are coextensive, and the aligned stack is placed in a Carver hydraulic press with metal platens heated to 120° C., the press is then closed and the stack is pressed at a pressure of 200 kPa for 60 seconds. The integrated building board sample is then removed from the press and allowed to cool. The final building board has an outer layer of WRB sheet attached to the board substrate via a polymeric bonding layer.

[0069] Example 3 This example uses the materials of Example 1, but demonstrates how to make a building board with an integral WRB sheet without the need to preassemble the WRB sheet and polymeric bonding layer into a two-material layer laminate.

[0070] A square gypsum board sample of 4 inches by 4 inches (10.2 cm by 10.2 cm) is cut from the DensGlass® Sheathing. Similarly, a square sample of the same size is cut from the WRB sheet, and a square sample of the same size is cut from the polymeric binder layer. As in Example 1, multiple layers of the polymeric binder layer can be used to achieve the desired basis weight of the polymeric binder layer. The polymeric binder layer sample is then placed in a stack on top of the square gypsum board sample, with one side of the polymeric binder layer sample in face-to-face contact with one of the faces of the gypsum board. The WRB sheet sample is then placed in a stack on top of the polymeric binder layer sample, again with one side of the WRB sheet sample in face-to-face contact with the other side of the polymeric binder layer sample.

[0071] The four edges of the WRB sheet, polymeric bonding layer, and gypsum board square specimen are then aligned so that they are coextensive, and the aligned stack is placed in a Carver hydraulic press with metal platens heated to 120° C. The press is then closed and the stack is pressed at 200 kPa pressure for 60 seconds. The integrated building board specimen with the integral WRB sheet is then removed from the press and allowed to cool.

[0072] Reference Example 1 This example shows that the fibrous web-like voids present in the polymeric bonding layer are maintained in the final building board with the integral WRB sheet. A series of integrated simulated building boards were made in the manner of Example 3, but for convenience, a single board with areas of different basis weights of the polymeric bonding layer was used to simulate a number of different board samples. In addition, these samples were made with a silicone-backed release paper rather than the WRB sheet of Example 1. The release paper was placed on top of the polymeric bonding layer in face-to-face contact with the face of the polymeric bonding layer, with the silicone-treated side of the release paper in contact with the polymeric bonding layer. In addition, a control sample area was provided on the board that included only the board and the silicone-backed release paper (no polymeric bonding layer material). The board samples were then consolidated in a press as described in Example 3. The board samples were then removed from the press, cooled, and the release liner was removed. The heat-activated polymeric bonding layer was then visible at the surface of the board, partially embedded in the glass fiber mat that was the finish material of the board. To better visualize the voids in the fiber web through the thickness of the polymeric bond layer after heat activation, black Dowsil™ 768 silicone sealant was applied to the surface of the board sample, and then excess sealant was removed using a metal spatula as a doctor blade. The remaining sealant remained in the voids in the fiber web through the thickness of the polymeric bond layer. The board is shown in FIG. 7 and is a 10 g / m 2 1 shows a first board sample 20 made from two layers of (0.3 osy) polymeric bond layers totaling 0.6 osy, a second board sample 21 having four layers of the same polymeric bond layers totaling 1.2 osy, a third board sample 22 having six layers of the same polymeric bond layers totaling 1.8 oz / sq yd, and a control board sample 23 having no polymeric bond layers. Thus, after heat activation and consolidation, the fibrous web-like voids through the thickness of the polymeric bond layers are maintained in the final building board with the integral WRB sheet.

[0073] Reference Example 2 This example shows how polymer modulus relates to the non-blocking properties of a two-layer laminate, allowing the laminate to be rolled, stored, and used without a release liner.

[0074] The polymer modulus was measured by dynamic mechanical analysis using an Anton Parr rheometer equipped with a CTD600 torsional rheology fixture run in oscillatory mode. Two types of non-tacky polymeric bonding layers were used, both of which were heat-activated fibrous webs obtained from Spunfab. Specifically, the polymeric bonding layers were 10 g / m 2 (0.3 osy) nominal basis weight and POF4002 with a nominal basis weight of 6 g / m 2 The polymer was PO4605 with a basis weight of 0.17 osy. Solid sheets of polymer from each bonded layer were obtained by heating and compression molding 30-40 layers of the fibrous web bonded layer. The resulting compressed samples were clear, free of visible air bubbles, and 2-3 mm thick.

[0075] Two typical hot melt adhesives commonly used to manufacture laminate structures in architectural applications were also tested: LA3 (Lanco Adhesives) and HMA6369 (Adhesive Compounders Inc). Both of these materials were tacky to the touch. A similar compression molding process was used to produce 2-3 mm thick specimens for evaluation. From each sample, rectangular specimens measuring 12.5 mm x 50 mm were cut for DMA evaluation.

[0076] The strain of the samples for testing was determined to be in the linear viscoelastic range using an amplitude sweep at a frequency of 1 rad / sec. The storage modulus and loss tangent (tan(d)) were then measured over a frequency range (ω=0.1-100 rad / sec) at the determined strain, typically 1-5% strain. Table 2 below reports the modulus of four different polymers recorded at a frequency (ω=0.1 rad / sec).

[0077] [Table 2]

[0078] Laminate samples were also prepared with each of the four hot melt polymers and evaluated for non-blocking of the laminate films when self-wound without a release liner. Testing was performed according to ISO 11502, Plastics - Films and Sheets - Determination of Blocking Resistance, Method A, by adhering or coating either the fibrous web polymeric tie layer POF4002 or PO4605, or the representative hot melt adhesive 6369 or LA-3, to a WRB sheet (also Tyvek® Commercial Wrap™). Briefly, laminate samples were prepared by sandwiching the polymeric tie layer or hot melt adhesive between two layers of WRB sheet (both printed and non-printed sides) and pressing in a 50°C oven with a weight equivalent to a pressure of 1 psi for 24 hours. After cooling, the samples are evaluated for whether the two layers of WRB sheet can be peeled away with minimal force. A pass means that the two layers of the WRB sheet easily separate, and a fail means that they do not separate under the specified peel conditions or separate with significant damage. As shown in Table 2, only samples that contain a bonding layer with a sufficiently high modulus that correlates with the deformability and adhesion of the polymer can pass the test.

[0079] Example 4 This example illustrates the improved seal obtained from the combination of WRB sheet and polymeric tie layer. As previously described in these examples, a series of building board specimens were prepared along with board specimen assemblies for fastener seal testing. All board substrates used were DensGlass® Sheathing. The WRB sheets (one specimen was Liquid WRB) and polymeric tie layer types are shown in Table 3. In the examples of the present invention, the polymeric tie layer used was 10 g / m 2 (0.3 osy) nominal basis weight and POF4002 with a nominal basis weight of 6 g / m 2The fibrous webs were PO4605 with a basis weight of 0.17 osy. One or more layers of these fibrous webs were used to make up the basis weight of the polymeric tie layer shown in Table 3. Examples 4-7 were calendered WRB sheets made from woven film strips that were further perforated to improve MVTR. The samples were building boards with integral WRB sheets, but did not have advanced sealing properties. It is believed that when the screws puncture the WRB sheets, the woven film structure of the WRB sheets tears, allowing water to penetrate the structure through other paths.

[0080] Examples 4-A and 4-B are comparative examples, neither of which passed the airtightness test described herein. For Example 4-A, the WRB sheet was the same as Examples 4-1 through 4-6, but the assembly did not include a polymeric bonding layer, and the WRB sheet was not bonded to the board in the test area. The WRB sheet was only bonded to the board around the edges with construction staples, and the screws were only driven into the WRB sheet and board, not through the polymeric bonding layer, since no polymeric bonding layer was present. Example 4-C is Securock® ExoAir® 430, an exterior gypsum board that was pre-coated with a liquid-applied WRB during manufacture. Thus, neither a durable WRB sheet material nor a polymeric bonding layer was used in this sample, and the screw heads tore through the soft WRB on the surface of the board, allowing water to penetrate under the liquid-applied WRB.

[0081] [Table 3]

[0082] Example 5 This example shows that the two-ply laminate of Example 1 can be applied to a magnesium oxychloride-based (magnesium oxide) building panel, with the resulting assembly exceeding the required water vapor transmission rate. Following the process outlined in Example 2, a 30 g / m 2Building board specimens were prepared comprising an outer layer of Tyvek Commercial Wrap WRB sheet attached to one side of the modified ArmorWall Sheathing via a POF4002 polymeric tie layer of 100% Tyvek Commercial Wrap WRB. ArmorWall Sheathing (available from DuPont) is a commercially available magnesium chloride cement composite board with foam attached to one side. For this evaluation, the foam was removed prior to testing. The water vapor transmission rate of the resulting assembly, evaluated using ASTM E96 Method B, was 6 palms.

Claims

1. 1. A method for providing a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, comprising: a) i) a WRB sheet having an inner surface and an outer surface, said WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a moisture vapor transmission rate of at least 40 grams per square meter per 24 hours; and ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, said polymeric bonding layer comprising a heat-activated or radio frequency activated fibrous web, said polymeric bonding layer further comprising voids through its thickness such that said polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of said WRB sheet; The polymer of the polymer bonding layer has a viscosity of 1×10 6 providing a polymeric tie layer having a modulus (G') greater than 100 Pa and a softening temperature greater than 122°F (50°C), said softening temperature being the temperature at which said polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; b) laminating the WRB sheet and the polymeric tie layer face-to-face so that the inner surface of the WRB sheet contacts the outer sheet surface of the polymeric tie layer; c) securing the polymeric bonding layer to the WRB sheet by heat energy, radio frequency energy, pressure, or a combination thereof to form a two-material layer laminate; d) furthermore, iii) providing a board substrate having an inner surface and an outer surface; e) laminating the two-material layer laminate and the board substrate face-to-face, with the inner sheet surface of the polymeric bonding layer in contact with the outer surface of the board substrate to form a non-integrated building board; f) bonding the two material layer laminate to the board substrate by applying heat or radio frequency energy along with pressure to the non-integrated building board to form an integrated building board having an inner surface and an outer surface, the board having a water vapor transmission rate of 5 parms or greater; A method comprising:

2. 1. A building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, said building board comprising: i) a WRB sheet having an inner surface and an outer surface, said WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a moisture vapor transmission rate of at least 40 grams per square meter per 24 hours; ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, said polymeric bonding layer comprising a heat-activated or radio frequency activated fibrous web, said polymeric bonding layer further comprising voids through its thickness such that said polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of said WRB sheet; The polymer of the polymer bonding layer has a viscosity of 1×10 6 a polymeric tie layer having a modulus (G') greater than 100 Pa and a softening temperature greater than 122°F (50°C), said softening temperature being the temperature at which said polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; iii) a board substrate having an inner surface and an outer surface; Including, i), ii), and iii), in turn, are joined together in an integrated building board; the WRB sheet is in face-to-face contact with the polymeric bonding layer, the inner surface of the WRB sheet being in contact with the outer sheet surface of the polymeric bonding layer; the board substrate is in face-to-face contact with the polymeric bonding layer, the inner sheet surface of the polymeric bonding layer being in contact with the outer surface of the board substrate; The water vapor transmission rate through the building board is 5 parms or more. Building board.

3. 1. A method for making a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, comprising: a) i) a WRB sheet having an inner surface and an outer surface, said WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a moisture vapor transmission rate of at least 40 grams per square meter per 24 hours; and ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, said polymeric bonding layer having a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard), said polymeric bonding layer comprising a heat-activated or radio frequency activated fibrous web, said polymeric bonding layer further having voids through its thickness such that said polymeric bonding layer has a moisture vapor transmission rate therethrough at least equal to or greater than that of said WRB sheet; The polymer of the polymer bonding layer has a viscosity of 1×10 6 a polymeric tie layer having a modulus (G') greater than 100 Pa and a softening temperature greater than 122°F (50°C), said softening temperature being the temperature at which said polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; and iii) a board substrate having an inner surface and an outer surface providing b) laminating i), ii), and iii) face-to-face so that the inner surface of the WRB sheet contacts the outer sheet surface of the polymeric bonding layer and the inner sheet surface of the polymeric bonding layer contacts the outer surface of the board substrate to form a non-integrated building board; c) bonding the non-integrated building boards with heat or radio frequency energy in conjunction with pressure to form an integrated building board having an inner surface and an outer surface, the integrated building board having a water vapor transmission rate through the board of at least 5 parms; A method comprising:

4. 1. A two-material layer laminate suitable for use in making a building board having an integral vapor-permeable water-resistant barrier (WRB) sheet, said two-material layer laminate comprising: i) a WRB sheet having an inner surface and an outer surface, said WRB sheet having a basis weight of 100 grams per square meter or less, a hydrostatic head of 55 cm or more, a Gurley Hill porosity of 250 seconds or more, and a moisture vapor transmission rate of at least 40 grams per square meter per 24 hours; ii) a polymeric bonding layer having an inner sheet surface and an outer sheet surface, said polymeric bonding layer having a basis weight of 17 to 70 grams per square meter (0.5 to 2 ounces per square yard), said polymeric bonding layer comprising a heat-activated or radio frequency activated fibrous web, said polymeric bonding layer further having fibrous web-like voids through its thickness such that said polymeric bonding layer has a moisture vapor transmission rate through said layer at least equal to or greater than that of said WRB sheet; The polymer of the polymer bonding layer has a viscosity of 1×10 6 a polymeric tie layer having a modulus (G') greater than 100 Pa and a softening temperature greater than 122°F (50°C), said softening temperature being the temperature at which said polymer modulus (G') drops to less than 30 percent of the polymer's modulus (G') at 20°C; Including, A two-material layer laminate, wherein the WRB sheet is secured face-to-face to the polymeric bonding layer, with the inner surface of the WRB sheet contacting the outer sheet surface of the polymeric bonding layer.

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