Self-adhesive roofing membrane

Abstract

The invention relates to a roofing membrane (1) comprising a waterproof layer (2), an adhesive layer (3) and optionally an isolation backing (4), wherein the adhesive layer (3) is an acrylic pressure sensitive adhesive layer. The invention also relates to a fully adhered roof system.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 201810937429.1. TECHNICAL FIELD

[0002] The present invention relates to the field of waterproofing above ground building structures by using self-adhesive roof membranes. In particular, the present invention relates to self-adhesive roof membranes which can be used to provide a fully adhered roof system. BACKGROUND

[0003] In the field of construction, polymeric sheets, commonly referred to as membranes, sheets or panels, are used to protect below and above ground buildings, such as basements, tunnels and flat and low-pitched roofs, from water penetration. For example, a waterproofing membrane is applied to prevent water ingress through cracks which are created in the concrete structure due to settlement of the building, off-loading or concrete shrinkage. Roof membranes for waterproofing flat and low-pitched roof structures are usually provided as single or multi-layer membrane systems. In single layer systems, the roof substrate is covered with a roof membrane consisting of a single waterproofing layer. In this case, the waterproofing layer usually contains a reinforcement layer to increase the mechanical stability of the roof membrane. In multi-layer membrane systems, a roof membrane comprising multiple waterproofing layers with similar or different compositions is used. Single layer membranes have the advantage of reduced production costs compared to multi-layer membranes, but they are also less resistant to mechanical damage caused by puncture by sharp objects.

[0004] Commonly used materials for roof membranes include plastics, in particular thermoplastics, such as plasticized polyvinyl chloride (p-PVC), thermoplastic olefins (TPE-O, TPO), and elastomers such as ethylene-propylene-diene monomer (EPDM). Roof membranes are usually delivered to the construction site in the form of a roll, transferred to the installation site, unrolled and adhered to the substrate to be waterproofed. The substrate on which the roof membrane is adhered can be composed of a variety of materials. The substrate can for example be a concrete, metal or wooden deck, or it can include an insulation board or recover board and / or an existing membrane.

[0005] Roof membranes have to be firmly fixed to the roof substrate to provide sufficient mechanical strength to resist the shear forces exerted on them due to high wind loads. Roof systems are usually classified into two categories depending on the way the roof membrane is fixed to the roof substrate. In mechanically connected roof systems, the roof membrane is fixed to the roof substrate by using screws and / or hooked plates. Mechanical fixation enables a high strength bond, but it only provides a direct connection to the roof substrate at the locations where the mechanical fasteners fix the membrane to the surface, which makes mechanically connected membranes prone to fluttering. In fully adhered roof systems, the membrane is usually adhered to the roof substrate indirectly using an adhesive composition.

[0006] Roofing membranes can be adhered to a roof substrate by using a variety of techniques, including contact bonding and the use of self-adhesive membranes. In contact bonding, the surfaces of the membrane and the roof substrate are first coated with a solvent or water-based contact adhesive, and then the membrane is brought into contact with the substrate surface. The volatile components of the contact adhesive are "flashed off" to provide a partially dried adhesive film before the membrane is brought into contact with the substrate. Fully adhered roof systems can also be prepared by using self-adhesive roofing membranes having a pre-applied adhesive composition layer coated on one of the outer surfaces of the membrane. Typically, the pre-applied adhesive layer is covered with a release liner to prevent premature unwanted adhesion and to protect the adhesive layer from moisture, dirt, and other environmental factors. In use, the release liner is removed and the roofing membrane is secured to the substrate without the use of additional adhesive. Roofing membranes having a pre-applied adhesive layer covered with a release liner are also referred to as "peel-and-stick membranes".

[0007] To create a continuous water-tight seal on the surface of the roof substrate, the edges of adjacent roofing membranes are overlapped to form sealable joints. These joints can then be sealed by bonding the bottom surface of the overlapped edge onto the top surface of another overlapped edge or by using a sealing tape that bridges the gap between the top surfaces of the two overlapped edges. The choice of technique for bonding the overlapped surfaces of adjacent membranes depends on the type of membrane. In the case of membranes composed of thermoplastic or non-crosslinked elastomeric materials, the overlapped portions of adjacent membranes can be bonded to each other by heat welding. In the case of self-adhesive membranes, the area near the longitudinal edges of the membrane is typically free of adhesive in order to enable the connection of the overlapped edges by heat welding. The overlapped portions of adjacent membranes can also be adhered to each other by using an adhesive.

[0008] Prior art self-adhesive roofing membranes based on plasticized polyvinyl chloride (p-PVC) typically contain a migration barrier between the water-proofing layer and the adhesive layer to prevent the migration of plasticizer from the water-proofing layer into the adhesive layer. The presence of the migration barrier increases the production cost of the roofing membrane. Furthermore, in the case of fully adhered roof systems, the joints between the overlapped edges of adjacent membranes are still typically sealed by heat welding or by using special sealing tapes, both of which increase the installation time and ultimately the installation cost.

[0009] Therefore, there is still a need for a self-adhesive roofing membrane that can be produced at a lower cost compared to prior art self-adhesive roofing membranes and that is capable of providing a fully adhered roof system while reducing the installation time and cost. SUMMARY

[0010] It is an object of the present invention to provide a self-adhesive roofing membrane that can be used to seal a roof substrate against water penetration.

[0011] It is another object of the present invention to provide a self-adhesive roofing membrane which can be used to provide a fully adhered roof system in which the joints between the overlapping edges of adjacent roofing membranes are adhesively bonded to each other.

[0012] The subject matter of the present invention is a roofing membrane as defined in claim 1.

[0013] It has surprisingly been found that a roofing membrane comprising a polyvinyl chloride based water-proofing layer and an acryl ic pressure sensitive adhesive layer coated on the surface thereof (which roofing membrane does not contain a migration barrier between the water-proofing layer and the adhesive layer) is able to solve or at least mitigate the problems of the prior art polyvinyl chloride based self-adhesive roofing membranes.

[0014] One advantage of the roofing membrane of the present invention is that it is able to provide a fully adhered roof system at lower production and installation costs compared to the prior art solutions.

[0015] Another advantage of the roofing membrane of the present invention is that it is able to provide a fully adhered roof system in which the joints between the overlapping edges of adjacent roofing membranes are adhesively bonded to each other using the same adhesive used for bonding the roofing membrane to the surface of the roof substrate.

[0016] Further aspects of the present invention are presented in the other independent claims. Preferred aspects of the present invention are presented in the dependent claims. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A cross-section of a roofing membrane (1) is shown which comprises a water-proofing layer (2), an adhesive layer (3) and a release liner (4) covering the outer major surface of the adhesive layer (3).

[0018] Figure 2 A cross-section of a roofing membrane (1) is shown which comprises a water-proofing layer (2), an adhesive layer (3), a release liner (4) covering the outer major surface of the adhesive layer (3) and a layer of fibrous material (5) fully embedded in the water-proofing layer (2).

[0019] Figure 3 A cross-section of a fully adhered roof system is shown which comprises a roof substrate (6) and a roofing membrane (1) comprising a water-proofing layer (2), an adhesive sealing layer (3) and a layer of fibrous material (5) fully embedded in the water-proofing layer (2), wherein the roofing membrane is directly bonded to the surface of the roof substrate (6) by the adhesive layer (3). DETAILED DESCRIPTION

[0020] The subject matter of the present invention is a self-adhesive roofing membrane (1) comprising:

[0021] i. a polyvinyl chloride based water-proofing layer (2) having first and second major surfaces, ii. an adhesive layer (3) coated on the first major surface of the water-proofing layer (2),

[0022] ii. an adhesive layer (3) coating and covering at least a portion of the second major surface of the waterproof layer (2), and

[0023] ii. Optional release liner (4), wherein the adhesive layer is an acrylic pressure-sensitive adhesive layer.

[0024] Substance names beginning with "poly" indicate substances that formally contain two or more of the functional groups mentioned in their names per molecule. For example, a polyol is a compound containing at least two hydroxyl groups. A polyether is a compound containing at least two ether groups.

[0025] The term "polymer" refers to a collection of chemically homogeneous macromolecules resulting from a polymerization reaction (polyaddition, polyaddition, polycondensation), wherein the macromolecules differ in their degree of polymerization, molecular weight and chain length. The term also includes derivatives of said collection of macromolecules resulting from polymerization, i.e. compounds obtained by reaction (e.g. addition or substitution) of functional groups in a predetermined macromolecule, and which may be chemically homogeneous or chemically heterogeneous.

[0026] The term "(meth)acrylic" refers to both methacrylic and acrylic compounds. Accordingly, "(meth)acryloyl" refers to either methacryloyl or acryloyl. (Meth)acryloyl is also known as (meth)acryloyl. (Meth)acrylic compounds may have one or more (meth)acryloyl groups, such as mono-, di-, tri-, etc. functional (meth)acrylic compounds.

[0027] The term "molecular weight" refers to the molar mass (g / mol) of a molecule or a portion of a molecule (also referred to as a "moiety"). The term "average molecular weight" refers to the number average molecular weight (M) of an oligomeric or polymeric mixture of molecules or moieties. n ). Molecular weight can be determined by gel permeation chromatography.

[0028] The term "softening point" refers to the temperature at which a compound softens to a rubbery state, or the temperature at which crystalline parts of a compound melt. The softening point can be determined by ring and ball measurement according to DIN EN 1238.

[0029] The term "melting temperature" refers to the crystalline melting point (T) determined by differential scanning calorimetry (DSC) using the method defined in ISO 11357 using a heating rate of 2°C / min. m ). The measurement can be performed using a Mettler Toledo DSC 3+ apparatus, and T can be determined from the measured DSC curve with the help of DSC software. m value.

[0030] The term "glass transition temperature" (T g ) indicates the temperature above which the polymer component becomes soft and flexible and below which it becomes hard and glassy. The glass transition temperature is preferably determined by dynamic mechanical analysis (DMA) as the peak value of the loss modulus (G") curve measured using an applied frequency of 1 Hz and a strain level of 0.1%.

[0031] The "amount or content of at least one component X" in the composition, for example "amount of at least one thermoplastic polymer", refers to the sum of the individual amounts of all thermoplastic polymers contained in the composition. Furthermore, in case the composition comprises 20 wt.% of at least one thermoplastic polymer, the total amount of all thermoplastic polymers contained in the composition equals 20 wt.%.

[0032] The term "room temperature" denotes a temperature of 23 °C.

[0033] The polyvinyl chloride-based water barrier layer is preferably a sheet-like element having first and second major surfaces, i.e. top and bottom surfaces.

[0034] The term "sheet-like element" refers herein to an element having a length and a width which are at least 25 times, preferably at least 50 times, more preferably at least 150 times the thickness of the element.

[0035] The adhesive layer is coated on the second major surface of the water barrier layer. Preferably, the water barrier layer and the adhesive layer are directly connected to each other on their opposite surfaces. The expression "directly connected" is to be understood in the context of the present application as meaning that there is no additional layer or substance between the layers and that the opposite surfaces of the layers are directly bonded to or adhered to each other. In the transition area between the two layers, the materials of the layers can also be present mixed with each other. In other words, there is no migration barrier between the water barrier layer and the adhesive layer.

[0036] Preferably, the adhesive layer covers at least 50%, more preferably at least 65%, most preferably at least 75% of the second major surface area of the water barrier layer. According to one or more embodiments, the adhesive layer and the water barrier layer have substantially the same width and length and / or the adhesive layer substantially covers the entire area of the second major surface of the water barrier layer. The term "substantially the entire area" is to be understood as meaning at least 85%, preferably at least 90%, more preferably at least 92%, most preferably at least 95% of the second major surface area of the water barrier layer. Furthermore, it can also be preferred, for example for production technical reasons, that narrow sections on the second major surface of the water barrier layer close to the longitudinal edges and having a width of 1-2 mm are free of the adhesive layer.

[0037] The adhesive layer is an acrylic pressure sensitive adhesive layer. In the present disclosure, the term "pressure sensitive adhesive (PSA)" means an adhesive composition that instantaneously adheres to most substrates by the application of slight pressure and remains permanently tacky. The term "acrylic adhesive" in the present disclosure means an adhesive composition containing one or more acrylic polymers as the main polymeric component.

[0038] Preferably, the acrylic pressure sensitive adhesive is a water-based acrylic dispersion pressure sensitive adhesive or a solvent-based acrylic pressure sensitive adhesive.

[0039] The term "water-based acrylic dispersion adhesive" in the present disclosure means an adhesive composition comprising one or more acrylic polymers that has been formulated as an aqueous dispersion or aqueous colloidal suspension. The term "water-based dispersion adhesive" means a dispersion adhesive containing water as the main continuous (carrier) phase.

[0040] The term "solvent-based acrylic adhesive" in the present disclosure means an adhesive composition comprising a solvent and one or more acrylic polymers that is substantially completely dissolved in the solvent. Typically, the solvent comprises at least 20 wt.%, preferably at least 30 wt.%, most preferably at least 40 wt.% of the total weight of the adhesive composition. Suitable solvents for solvent-based acrylic adhesives include, for example, alcohols, aliphatic and aromatic hydrocarbons, ketones, esters, and mixtures thereof. Only a single solvent or a mixture of two or more solvents can be used. Suitable solvent-based acrylic adhesives are substantially free of water, for example, those containing less than 10 wt.%, preferably less than 5 wt.%, more preferably less than 1 wt.% water, based on the total weight of the adhesive composition.

[0041] The term "acrylic polymer" in the present disclosure means homopolymers, copolymers, and higher interpolymer of acrylic monomers with one or more other acrylic monomers and / or with one or more other vinylic unsaturated monomers. The term "acrylic monomer" in the present disclosure means a monomer having at least one (meth)acryloyl group in the molecule. Examples of acrylic monomers include, for example, (meth)acrylate, (meth)acrylic acid, or derivatives thereof, such as amides of (meth)acrylic acid or nitriles of (meth)acrylic acid, and (meth)acrylate esters having functional groups such as hydroxyalkyl (meth)acrylate esters, and hydroxyl-containing (meth)acrylate esters. Preferably, the acrylic polymer contains acrylic monomers as the main monomer component, i.e., the acrylic polymer contains at least 30 wt.%, preferably at least 40 wt.%, more preferably at least 50 wt.% of acrylic monomers.

[0042] Particularly suitable acrylic polymers contain (meth)acrylic acid alkyl esters, preferably (meth)acrylates of alcohols containing 1 to 24 carbon atoms, as the main monomer component. In the acrylic polymers, more than 25 wt.%, preferably more than 35 wt.% of these types of acrylic monomers are preferred. Examples of particularly suitable (meth)acrylic acid alkyl esters include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate, n-butyl methacrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate, n-octyl acrylate, n-octyl methacrylate, n-nonyl acrylate, lauryl acrylate, stearyl acrylate, behenyl acrylate, and branched isomers thereof, such as, for example, isobutyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, isooctyl acrylate, isooctyl methacrylate, and cyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, or 3,5-dimethyladamantyl acrylate.

[0043] Suitable comonomers for use with the (meth)acrylic acid alkyl esters include, in particular, acrylic monomers containing hydroxyl groups and hydroxyalkyl groups. Examples of suitable acrylic monomers containing hydroxyl groups and hydroxyalkyl groups include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxyhexyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate. In addition, suitable are (4-hydroxymethylcyclohexyl)methyl methacrylate, polypropylene glycol mono(meth)acrylate, N-hydroxyethyl (meth)acrylamide, and N-hydroxypropyl (meth)acrylamide. Acrylic monomers containing hydroxyl groups and hydroxyalkyl groups are preferably used in the range of 0.01 to 15 wt.%, more preferably 0.1 to 10 wt.%, based on the total amount of monomers used in the synthesis of the acrylic polymers.

[0044] Other suitable comonomers for the acrylic polymers include vinyl compounds, in particular vinyl esters, vinyl halides, vinylidene halides, functionally group-containing olefinically unsaturated hydrocarbons, and nitriles of olefinically unsaturated hydrocarbons. Examples of suitable vinyl compounds include, for example, maleic anhydride, styrene, styrene compounds, beta-acryloyloxypropionic acid, vinyl acetic acid, fumaric acid, crotonic acid, aconitic acid, trichloroacrylic acid, itaconic acid, and vinyl acetate.

[0045] According to one or more embodiments, the adhesive layer comprises at least 75 wt.%, preferably at least 85 wt.%, more preferably at least 90 wt.%, most preferably at least 95 wt.% of at least one acrylic polymer, based on the total weight of the adhesive layer.

[0046] Preferably, the at least one acrylic polymer has a glass transition temperature (T g ) below 0°C, preferably less than -20°C. g The glass transition temperature (T n ) is determined by dynamic mechanical analysis (DMA) using an applied frequency of 1 Hz and a strain level of 0.1%.

[0047] Preferably, the at least one acrylic ester polymer has an average molecular weight (M n ) in the range of 50 000 - 1 000 000 g / mol, in particular 100 000 - 750 000 g / mol, more preferably 150 000 - 500 000 g / mol.

[0048] In addition to the at least one acrylic polymer, the adhesive layer can comprise one or more additional ingredients, including for example tackifying resins, waxes and plasticizers as well as one or more additives, such as UV light absorbers, UV and heat stabilizers, optical brighteners, pigments, dyes and drying agents. Preferably, the amount of additional ingredients and additives is not more than 15 wt.%, more preferably not more than 10 wt.%, most preferably not more than 5 wt.%, based on the total weight of the adhesive layer.

[0049] The preferred thickness of the adhesive layer depends on the detailed composition of the adhesive. According to one or more embodiments, the adhesive layer has a thickness of 25 - 500 pm, preferably 50 - 250 pm, more preferably 75 - 200 pm, determined by using the measurement method defined in the DIN EN 1849-2 standard. Preferably, the second main surface of the waterproofing layer is coated with a continuous adhesive layer. The term "continuous layer" in the present disclosure refers to a layer consisting of one single area coated with adhesive, whereas a "discontinuous layer" is considered to consist of several isolated areas coated with adhesive.

[0050] The detailed composition of the waterproofing layer is not particularly limited. However, the composition of the waterproofing layer should be chosen such that the roofing membrane meets the general requirements for roofing membranes providing a fully adhered roof system, in particular the general requirements defined in DIN 20000-201 :2015-08.

[0051] For example, it may be preferred to choose the composition of the waterproofing layer such that the roofing membrane exhibits an impact resistance in the range of 200-1500 mm measured according to EN 12691:2005, and / or a longitudinal and transverse tensile strength of at least 5 MPa measured at a temperature of 23° C. according to DIN ISO 527-3 and / or an elongation at break in the longitudinal and transverse directions of at least 300% measured at a temperature of 23° C. according to DIN ISO 527-3 and / or a water resistance of 0.6 bar for 24 hours measured according to EN 1928B and / or a maximum tear strength of at least 100 N measured according to EN 12310-2.

[0052] According to one or more embodiments, the waterproof layer comprises:

[0053] a) 25-65 wt.%, preferably 30-60 wt.% of polyvinyl chloride resin,

[0054] b) 15-50 wt.%, preferably 20-40 wt.% of at least one plasticizer, and

[0055] c) 0-30 wt.%, preferably 0-20 wt.% of at least one inert mineral filler, all proportions being based on the total weight of the waterproof layer.

[0056] Preferably, the polyvinyl chloride resin has a K value of 50 to 85, more preferably 65 to 75, as determined by the method described in ISO 1628-2-1998. The K value is a measure of the polymerization grade of the PVC resin and is determined by the viscosity value of the PVC homopolymer as the original resin, dissolved in cyclohexanone at 30°C.

[0057] Preferably, the composition of the waterproof layer has a glass transition temperature (T g ), the glass transition temperature (T g ) were determined by dynamic mechanical analysis (DMA) using an applied frequency of 1 Hz and a strain level of 0.1%.

[0058] The type of at least one plasticizer is not particularly limited in the present application. Plasticizers suitable for use with PVC resins include, but are not limited to, for example, straight or branched chain phthalates such as diisononyl phthalate (DINP), di-nonyl phthalate (L9P), di-allyl phthalate (DAP), di-2-ethylhexyl phthalate (DEHP), dioctyl phthalate (DOP), diisodecyl phthalate (DIDP), and mixed linear phthalates (911P). Other suitable plasticizers include non-phthalate plasticizers, such as trimellitate plasticizers, adipate polyesters, and bio-based plasticizers. Examples of bio-based plasticizers include epoxidized vegetable oils, such as epoxidized soybean oil and epoxidized linseed oil, and acetylated waxes and oils derived from plants, such as acetylated castor wax and acetylated castor oil.

[0059] Particularly suitable non-phthalate plasticizers for the water barrier layer include alkyl esters of benzoic acid, dialkyl esters of aliphatic dicarboxylic acids, polyesters of aliphatic dicarboxylic acids or aliphatic di-, tri-, and tetrols, which are not esterified at the end groups or have been esterified with monofunctional reagents, trialkyl citrates, acetylated trialkyl citrates, glycerol esters, benzoic acid diesters of mono-, di-, tri-, or polyalkylene glycols, trimethylolpropane esters, dialkyl cyclohexane dicarboxylates, dialkyl esters of terephthalic acid, trialkyl esters of trimellitic acid, triaryl esters of phosphoric acid, diaryl alkyl esters of phosphoric acid, trialkyl phosphates, and aryl esters of alkane sulfonic acids.

[0060] According to one or more embodiments, the at least one plasticizer is selected from the group consisting of phthalates, trimellitate plasticizers, adipate polyesters, and bio-based plasticizers.

[0061] The term "inert mineral filler" means herein a mineral filler which, unlike mineral binders, does not react with water, i.e. does not undergo a hydration reaction in the presence of water. Preferably, the at least one inert mineral filler is selected from the group consisting of sand, granite, calcium carbonate, clay, expanded clay, diatomite, pumice, mica, kaolin, talc, dolomite, xonotlite, perlite, vermiculite, wollastonite, barite, magnesium carbonate, calcium hydroxide, calcium aluminate, silica, fumed silica, fused silica, aerogel, glass beads, hollow glass spheres, ceramic spheres, bauxite, ground concrete, and zeolite.

[0062] The term "sand" refers herein to mineral clastic sediments (clastic rocks) which are loose conglomerates (loose sediments) of round or angular small particles which are separated from the original grain structure during mechanical and chemical degradation processes and transported to their point of deposition, the Si02content of which is greater than 50 wt.%, in particular greater than 75 wt.%, particularly preferably greater than 85 wt.%. The term "calcium carbonate" as an inert mineral filler refers herein to calcite fillers produced by grinding and / or precipitation from chalk, limestone or marble.

[0063] According to one or more embodiments, the at least one mineral filler is present in the waterproofing layer in an amount of 5-30 wt.%, preferably 10-30 wt.%, more preferably 15-30 wt.%, based on the total weight of the waterproofing layer.

[0064] The waterproofing layer can further comprise one or more additives, such as UV and heat stabilizers, antioxidants, flame retardants, dyes, pigments such as titanium dioxide and carbon black, matting agents, antistatic agents, impact modifiers, biocides and processing aids such as lubricants, slip agents, anti-blocking agents and denes t aids.

[0065] The thickness of the waterproofing layer is not particularly limited. According to one or more embodiments, the thickness of the waterproofing layer is 0.25-5.0 mm, preferably 0.5-4.5 mm, more preferably 1.0-3.0 mm, most preferably 1.0-2.5 mm, said thickness being determined by using the measuring method defined in the DIN EN 1849-2 standard.

[0066] According to one or more embodiments, the roofing membrane further comprises a layer of fibrous material which is completely embedded in the waterproofing layer. The expression "completely embedded" means that the layer of fibrous material is completely covered by the matrix of the waterproofing layer. The layer of fibrous material can serve to ensure the mechanical stability of the waterproofing layer when the roofing membrane is exposed to varying environmental conditions, in particular large temperature fluctuations.

[0067] The term "fibrous material" denotes herein a material consisting of fibers comprising or consisting of, for example, organic, inorganic or synthetic organic materials. Examples of organic fibers include, for example, cellulose fibers, cotton fibers and protein fibers. Particularly suitable synthetic organic materials include, for example, homo- and copolymers of polyesters, ethylene and / or propylene, viscose, nylon and polyamides. Fibrous materials consisting of inorganic fibers are also suitable, in particular those consisting of metal fibers or mineral fibers, such as glass fibers, aramid fibers, wollastonite fibers and carbon fibers. Inorganic fibers which have been surface treated, for example, with silanes can also be suitable. The fibrous material can comprise staple fibers, long fibers, staple fibers (yarns) or filaments. The fibers can be oriented or stretched fibers. It can also be advantageous for the fibrous material to consist of different types of fibers in terms of geometry and composition.

[0068] Preferably, the layer of fibrous material is selected from the group consisting of nonwoven, woven fabric and nonwoven scrims.

[0069] The term "nonwoven" denotes herein a material consisting of fibers which are bonded together by using chemical, mechanical or thermal bonding means and which are neither woven nor knitted. Nonwovens can be produced, for example, by using a carding or needle punching process, wherein the fibers are mechanically entangled to obtain a nonwoven. In chemical bonding, chemical binders such as adhesive materials are used to hold the fibers in the nonwoven.

[0070] The term "nonwoven scrim" denotes herein a web-like nonwoven product consisting of yarns which are laid on top of each other and chemically bonded to each other. Typical materials used for nonwoven scrims include metals, glass fibers and plastics, in particular polyesters, polypropylene, polyethylene and polyethylene terephthalate (PET).

[0071] According to one or more embodiments, the layer of fibrous material is a nonwoven, preferably a nonwoven, more preferably a nonwoven having a mass per unit weight of not more than 250 g / m2, preferably not more than 200 g / m2. 2 According to one or more embodiments, the layer of fibrous material is a nonwoven having a mass per unit weight of 15-150 g / m2, preferably 20-125 g / m2, more preferably 25-100 g / m2, most preferably 30-85 g / m2. 2 According to one or more embodiments, the layer of fibrous material is a nonwoven having a mass per unit weight of 15-150 g / m2, preferably 20-125 g / m2, more preferably 25-100 g / m2, most preferably 30-85 g / m2. 2 According to one or more embodiments, the layer of fibrous material is a nonwoven having a mass per unit weight of 15-150 g / m2, preferably 20-125 g / m2, more preferably 25-100 g / m2, most preferably 30-85 g / m2. 2 According to one or more embodiments, the layer of fibrous material is a nonwoven having a mass per unit weight of 15-150 g / m2, preferably 20-125 g / m2, more preferably 25-100 g / m2, most preferably 30-85 g / m2. 2 According to one or more embodiments, the layer of fibrous material is a nonwoven having a mass per unit weight of 15-150 g / m2, preferably 20-125 g / m2, more preferably 25-100 g / m2, most preferably 30-85 g / m2. 2 According to one or more embodiments, the layer of fibrous material is a nonwoven having a mass per unit weight of 15-150 g / m2, preferably 20-125 g / m2, more preferably 25-100 g / m2, most preferably 30-85 g / m2.

[0072] Preferably, the nonwoven fabric of the fibrous material layer comprises synthetic organic and / or inorganic fibers. Particularly suitable synthetic organic fibers for the nonwoven fabric include, for example, polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers, and polyamide fibers. Particularly suitable inorganic fibers for the nonwoven fabric include, for example, glass fibers, aramid fibers, wollastonite fibers, and carbon fibers.

[0073] According to one or more embodiments, the nonwoven fabric of the fibrous material layer has synthetic organic fibers as the main fiber component, preferably selected from the group consisting of polyester fibers, polypropylene fibers, polyethylene fibers, nylon fibers, and polyamide fibers. According to one or more further embodiments, the nonwoven fabric of the fibrous material layer has inorganic fibers as the main fiber component, preferably selected from the group consisting of glass fibers, aramid fibers, wollastonite fibers, and carbon fibers, more preferably glass fibers.

[0074] According to one or more embodiments, the roofing membrane further comprises a release liner covering at least a portion of the outer major surface of the adhesive layer facing away from the second major surface of the waterproofing layer. Preferably, the adhesive layer and the release liner are directly connected to each other over at least a portion of their opposing major surfaces. The release liner can serve to prevent premature unwanted adhesion and to protect the adhesive layer from moisture, dirt, and other environmental factors. In case the roofing membrane is provided in the form of a roll, the release liner makes it easy to unroll without sticking the adhesive to the backside of the roofing membrane. The release liner can be cut into sections to allow the liner to be separated from the adhesive layer in sections.

[0075] Suitable materials for the release liner include kraft paper, polyethylene-coated paper, silicone-coated paper, and polymeric films, such as polyethylene, polypropylene, and polyester films, which are coated with a polymeric release agent selected from the group consisting of silicones, silicone ureas, urethanes, waxes, and long-chain alkyl acrylate release agents.

[0076] The roofing membrane of the present application can be a single-ply or a multi-ply roofing membrane. The term "single-ply roofing membrane" denotes herein a membrane comprising one single waterproofing layer, whereas the term "multi-ply roofing membrane" denotes a membrane comprising more than one waterproofing layer. In case of a multi-ply roofing membrane, the waterproofing layers can have similar or different compositions.

[0077] Single-ply and multi-ply membranes are known to the person skilled in the art and they can be produced by any conventional method, for example by extrusion or co-extrusion, calendering, or by brush coating. According to one or more embodiments, the roofing membrane is a single-ply membrane, which comprises exactly one waterproofing layer.

[0078] According to one or more further embodiments, the roofing membrane is a multi-layer membrane comprising at least two, preferably two, water barrier layers. In these embodiments, the roofing membrane further comprises a second water barrier layer having first and second major surfaces, wherein the second major surface of the second barrier layer is directly or indirectly bonded to at least a portion of the first major surface of the water barrier layer.

[0079] According to one or more embodiments, the second water barrier layer is a polyvinyl chloride based water barrier layer. Preferably, the second water barrier layer has a substantially similar composition as the water barrier layer. The second water barrier layer can also comprise a layer of fibrous material which is completely embedded in the second water barrier layer. However, it is also possible or even preferred that the second water barrier layer does not comprise a layer of fibrous material which is completely embedded in the second water barrier layer.

[0080] Preferably, the roofing membrane has a 90° peel resistance on stainless steel of at least 5 N / 50 mm, more preferably at least 10 N / 50 mm, most preferably at least 15 N / 50 mm, measured by using the method defined by the EN DIN 1372 standard. Such peel strengths have been found with the adhesive layer as defined above.

[0081] The roofing membrane of the present application is typically provided in the form of a pre-fabricated membrane article which is delivered to the construction site and unrolled from a roll to provide a sheet having a width of 1-5 meters and a length which is several times the width. However, the roofing membrane can also be used in the form of a strip having a width of typically 1-20 cm, for example in order to seal a joint between two adjacent membranes. Furthermore, the roofing membrane can also be provided in the form of a flat body which is used to repair a damaged location in an already adhered water barrier or roofing system.

[0082] The preferred options for the water barrier layer, the adhesive layer, the layer of fibrous material and the release liner given above apply equally to all aspects of the present application, unless otherwise stated.

[0083] Another subject matter of the present application is a fully adhered roofing system comprising a roofing substrate and a roofing membrane according to the present application which is directly adhered to the surface of the roofing substrate by means of the adhesive layer. The expression "directly adhered" is understood to mean that there is no other layer between the adhesive layer and the roofing substrate.

[0084] The roofing substrate to which the roofing membrane is bonded is preferably selected from the group consisting of an insulation board, a cover board and an already existing roofing membrane.

[0085] According to one or more embodiments, at least 50%, preferably at least 75%, most preferably at least 85% of the area of the second major surface of the water barrier layer is adhered to the surface of the roofing substrate by means of the adhesive layer. According to one or more embodiments, substantially the entire area of the second major surface of the water barrier layer is adhered to the surface of the roofing substrate by means of the adhesive layer.

[0086] Detailed description of the figures

[0087] Figure 1 A cross-section of a roofing membrane (1) is shown, comprising a waterproof layer (2), an adhesive layer (3), and a release liner (4) covering the outer major surface of the adhesive layer (3). In this embodiment, the adhesive layer (3) covers substantially the entire area of ​​the second major surface of the waterproof layer (2), and the release liner (4) covers substantially the entire area of ​​the outer major surface of the adhesive layer (3) facing away from the second major surface of the waterproof layer (2).

[0088] Figure 2 Shows the Figure 1 A cross section of a roofing membrane (1) of one embodiment of the roofing membrane is presented in . In this embodiment, the roofing membrane (1) further comprises a layer of fibrous material (5) which is completely embedded in the waterproof layer (2).

[0089] Figure 3 A cross-section of a fully adhered roofing system is shown, comprising a roofing substrate (6) and a roofing membrane (1), the roofing membrane (1) being adhered directly to the surface of the roofing substrate (6) via an adhesive layer (3). In this embodiment, substantially the entire area of ​​the second major surface of the waterproof layer (2) is adhered to the surface of the roofing substrate (6) via the adhesive layer (3). In addition, the roofing membrane (1) further comprises a fibrous material layer (5) which is completely embedded in the waterproof layer (2). Example

[0090] Preparation of roofing membranes

[0091] By using 140g / m 2 A roofing membrane according to the invention was prepared by coating a PVC film Sarnafil G410-15 (available from Sika AG) having a nominal thickness of 1.5 mm with a layer of a water-based acrylic dispersion pressure-sensitive adhesive of a coating weight of 1.5 mm. The applied adhesive layer was covered with a siliconized PE release liner having a thickness of 80 μm.

[0092] By using 140g / m 2 A reference roofing membrane was prepared by coating a PVC film Sarnafil G410-15 (available from Sika AG) with a styrene block copolymer (SBS / SIS) based hot melt pressure sensitive adhesive of a coating weight of 1000 Å. The applied adhesive layer was covered with a siliconized PE release liner having a thickness of 80 μm.

[0093] Both roofing membranes were stored at a temperature of 80°C for 4 weeks before measuring the peel strength obtained with the adhesive layer.

[0094] Resistance to peeling (strength)

[0095] The resistance to delamination from a metal surface was measured using the method defined in the EN DIN 1372 standard. In the resistance to delamination measurement, a Zwick tensile testing apparatus and a constant crosshead speed of 100 mm / min were used to peel a sample strip of the tested roofing membrane at a 90° peel angle. The average resistance to delamination was calculated as the average peel force [N / 50 mm] over the width of each strip during the period in which approximately 10 cm of length was peeled, thus excluding the first and last fifth of the total peeling length from the calculation. The average resistance to delamination value was calculated as the average of the measurements obtained with two similar roofing membranes.

[0096] In the case of the roofing membrane of the application, an average resistance to delamination of 28 N / 50 mm was obtained, while the reference roofing membrane showed a complete loss of adhesion due to migration of the plasticizer from the PVC film to the adhesive layer.

Claims

1. Self-adhesive roofing membrane (1), comprising: i. a polyvinyl chloride-based waterproof layer (2) having a first and a second major surface, ii. an adhesive layer (3) coating and covering at least a portion of the second major surface of the waterproof layer (2), iii. Optional release liner (4), characterized in that The adhesive layer is an acrylic pressure-sensitive adhesive. wherein the adhesive layer (3) comprises at least 95 wt. % of at least one acrylic polymer, based on the total weight of the adhesive layer; and The waterproof layer (2) comprises: a) 25-65 wt.% of polyvinyl chloride resin, b) 15-50 wt.% of at least one plasticizer, and c) 0-30 wt.% of at least one inert mineral filler, all proportions being based on the total weight of the waterproof layer (2).

2. The self-adhesive roofing membrane according to claim 1, characterized in that The adhesive layer (3) covers at least 85% of the entire area of ​​the second major surface of the waterproof layer (2).

3. The self-adhesive roofing membrane according to claim 1, characterized in that The at least one acrylic polymer has a glass transition temperature below 0°C as determined by dynamic mechanical analysis using an applied frequency of 1 Hz and a strain level of 0.1%.

4. The self-adhesive roofing membrane according to claim 3, characterized in that The at least one acrylic polymer has a glass transition temperature below -20°C.

5. The self-adhesive roofing membrane according to claim 1, characterized in that The adhesive layer (3) has a thickness of 25-500 μm, which is determined by using the measurement method defined in the DIN EN 1849-2 standard.

6. The self-adhesive roofing membrane according to claim 5, characterized in that The adhesive layer (3) has a thickness of 50-250 μm.

7. The self-adhesive roofing membrane according to claim 1, characterized in that The waterproof layer composition has a glass transition temperature of less than -20°C, as determined by dynamic mechanical analysis using an applied frequency of 1 Hz and a strain level of 0.1%.

8. The self-adhesive roofing membrane according to claim 7, characterized in that The waterproof layer composition has a glass transition temperature lower than -25°C.

9. The self-adhesive roofing membrane according to claim 1, characterized in that The at least one plasticizer is selected from the group consisting of linear and branched phthalates, trimellitate plasticizers, adipic acid polyesters, and biochemical plasticizers.

10. The self-adhesive roofing membrane according to claim 1, characterized in that The at least one inert mineral filler is selected from the group consisting of sand, granite, calcium carbonate, clay, diatomaceous earth, pumice, mica, kaolin, talc, dolomite, xonotlite, perlite, vermiculite, wollastonite, barite, magnesium carbonate, calcium hydroxide, calcium aluminate, silica, aerogel, glass beads, hollow glass spheres, ceramic spheres, bauxite, crushed concrete and zeolites.

11. The self-adhesive roofing membrane according to claim 10, characterized in that The at least one inert mineral filler is selected from expanded clay, fumed silica and fused silica.

12. The self-adhesive roofing membrane according to any one of claims 1 to 6, characterized in that The waterproof layer (2) has a thickness of 0.5-5.0 mm, which is determined by using the measurement method defined in the DIN EN 1849-2 standard.

13. The self-adhesive roofing membrane according to claim 12, characterized in that The waterproof layer (2) has a thickness of 1.0-2.5 mm.

14. The self-adhesive roofing membrane according to any one of claims 1 to 6, characterized in that It further comprises a layer of fibrous material (5) completely embedded in the waterproof layer (2).

15. The self-adhesive roofing membrane according to claim 14, characterized in that The fiber material layer (5) has a unit area mass of 15-150 g / m 2 non-woven fabric.

16. The self-adhesive roofing membrane according to claim 14, characterized in that The fiber material layer (5) has a unit area mass of 25-100 g / m 2 non-woven fabric.

17. The self-adhesive roofing membrane according to claim 15, characterized in that The nonwoven fabric contains inorganic fibers.

18. The self-adhesive roofing membrane according to claim 15, characterized in that The nonwoven fabric contains glass fibers.

19. The self-adhesive roofing membrane according to any one of claims 1 to 6, characterized in that It further comprises a release liner (4) covering at least a portion of the outer major surface of the adhesive layer (3) facing away from the second major surface of the waterproof layer (2).

20. A fully adhered roofing system comprising a roofing substrate (6) and a self-adhesive roofing membrane (1) according to any one of claims 1 to 19 directly adhered to the surface of the roofing substrate (6) via an adhesive layer (3).

21. The fully adhered roof system according to claim 20, characterized in that The roof substrate (6) is selected from insulation boards, cover boards and existing roofing membranes.

22. A fully adhered roof system according to claim 20 or 21, characterised in that At least 50% of the entire area of ​​the second major surface of the waterproof layer (2) is bonded to the surface of the roofing substrate (6) via the adhesive layer (3).

23. The fully adhered roof system according to claim 22, characterized in that At least 75% of the entire area of ​​the second major surface of the waterproof layer (2) is bonded to the surface of the roofing substrate (6) via the adhesive layer (3).

24. The fully adhered roof system according to claim 22, characterized in that At least 85% of the entire area of ​​the second major surface of the waterproof layer (2) is bonded to the surface of the roofing substrate (6) via the adhesive layer (3).

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