FR2650615A1 - PREFABRICATED ACRYLIC SEALING MATERIAL AND ITS APPLICATION IN SEALING COVERS AND UNDERCOVERINGS - Google Patents

Abstract

A prefabricated multi-layered sheet acrylic sealant, wherein said sheet has a layer of a textile backing, a layer of a foam of an acrylic polymeric material and a layer of a binder of an acrylic polymeric material, each layer being bonded to at least one of the other two layers so that the foam layer is always in contact with the textile support layer. Application of the sheet material for the waterproofing of roofs or as an underlay material.

Description

The invention relates to a prefabricated acrylic sealing material

  multilayer sheet and still relates to the application of this material to the production of

  the waterproofness of blankets and under-covers.

  Various prefabricated sealing materials have already been proposed in multilayer sheet for the realization of the waterproofness of covers. buildings and especially rooftop terraces. Thus, the FR-A1483973 discloses a sealed cover element, which consists of a sheet consisting of a plastic or elastic sealing membrane against-glued on a flexible sheet of cellular foam open cell, said element being placed by gluing the foam side, by means of a suitable glue, to the support whose sealing is to be achieved. FR-A-2362981 relates, inter alia, to an acrylic sealing material formed of a layer of a textile material 'coated on one of its faces with an impermeable layer made of an acrylic polymeric material, said sealing material is bonded by bonding on the textile side, by means of a suitable adhesive, to the support to be sealed, so that a central part of the textile layer is not impregnated by the adhesive used for the collage, nor by the material

  Acrylic polymer of the waterproof layer.

  Also known (FR-A-2467934 and FR-A-2517726) a waterproof, watertight and vapor permeable underframe material for roofs in discrete elements such as tiles or slates overlapping each other, said material consisting of a nonwoven web of fibers of a polymeric material such as polypropylene, polyethylene, polyester, vinyl polymer, heat-coated on one side (FR-A-2467934) or on its two faces (FR-A-2517726), a film of fillerised bitumen in an amount just sufficient to present to cooling a microtreated or microcracked structure opposing the passage of liquid by capillarity, but allowing the passage of air or steam; Despite their interesting performance, the prefabricated multilayer sheet sealing materials proposed for the realization of the waterproofness of

  roofs of buildings or as substandard materials

  roofs or under-roofs still have some shortcomings. In particular, the material described in FR-A-1483973 has a low resistance to static punching, determined according to standard NF P 84352, and in addition the open cells of the foam constitute a serious defect in case of leakage (effect- sponge and accumulation of large amounts of water). For the sub-roofing bituminous material of the FR-A-2467934 and FR-A-2517726, the well-known sensitivity of UV bitumen requires an implementation of the coverage without delay, the product losing

  also some of its flexibility in cold weather.

  The invention provides a prefabricated acrylic sealing material which is present under the. form of a multilayer sheet, which is used to achieve the sealing of building roofs or as undercladding material. or under-roofing and which in each of said applications makes it possible to remedy

  shortcomings of the sheet materials used until then.

  The prefabricated acrylic sealing material according to the invention consists of a multilayer sheet which is characterized in that it comprises a layer of a textile support, a layer of a foam made of an acrylic polymeric material and a layer of a binder of an acrylic polymer material, each layer being bonded to at least one of the other two layers so that the layer of foam is

  always in contact with the textile support layer.

  Advantageously, the thicknesses of the different layers of the multilayer film correspond to surface densities of said layers ranging from 30 to 300 g / m 2 for the textile support layer, from 10 to 100 g / m 2 for the

  foam and from 50 to 2000 g / m2 for the binder layer.

2 50615

  The textile backing layer may consist of a woven or preferably non-woven web of natural or synthetic organic fibers, for example fibers made of a polymeric material such as polypropylene, polyethylene, polyamide and especially aromatic polyamide, polyester, vinyl polymer, or even of inorganic fibers ,. by

example glass fibers.

  The acrylic polymeric material used to constitute the foam layer is based on at least one polymer chosen from homopolymers of acrylic esters, copolymers of acrylic esters with one another and copolymers of one or more acrylic esters with a quantity of a minority of one or more ethylenically unsaturated monomers such as ethylenically unsaturated carboxylic acids and their anhydrides, especially acrylic acid, methacrylic acid, maleic anhydride, crosslinking monomers such as acrylic amides, for example acrylamide, methylolacrylamide, vinylaromatic monomers such as styrene, said copolymers being random copolymers, graft copolymers or even block copolymers. The acrylic esters which are part of the composition of the abovementioned polymers are advantageously alkyl acrylates or methacrylates whose alkyl radical is C 1 to C 18 and preferably C 2 to C 8, especially ethyl, butyl, hexyl and 2-ethyl hexyl. , and may carry, optionally, at least one functional group, for example a grouping

hydroxyl or amino.

  The polymeric material from which the binder layer is formed is based on at least one acrylic polymer chosen from the homopolymers and copolymers defined above.

  high as likely to form the foam layer.

  The polymer (s) constituting the polymeric material of the binder layer may be identical or partially identical to the polymers forming the polymeric material of the foam layer or, conversely, different

of these last polymers.

26506 15

  In addition to its polymer component, each of the layers of foam and binder may also contain various additives, for example fillers such as kaolin and calcium carbonate, pigments, dyes, flame retardants, wetting agents, fungicides, algicides, the said additives being associated with the polymer component of the layer concerned in amounts corresponding to those usually recommended for their use. Advantageously, the binder layer of the multilayer sheet constituting the sealing material contains a few percent. for example 2 to 5%, by weight of a granular filler, in particular glass microspheres, silicate, calcium carbonate, whose grain size is from about 1 μm to 600 μm, which makes it possible to impart a micro-roughness

surface to the binder layer.

  According to a first embodiment, the sealing material according to the invention has its foam layer interposed between its textile support layer and its layer. of

  binder, the thicknesses of said layers corresponding to

  surface weights ranging from 30 to 300 g / m 2 for the textile backing layer, from 10 to 100 g / m 2 for the foam layer and from 1000 to 2000 g / m 2 for the binder layer. In particular, in this first embodiment, the foam layer has a cellular gradient from the textile layer to the binder layer, i.e. has a decreasing number of cells, from the layer. textile, as and when approaching the binder layer to arrive, in contact with said binder layer, to a continuous and closed surface. The multilayer sheet sealing material obtained according to the above-mentioned first embodiment can be used for sealing roofs, in particular flat roofs, such a material having a total watertightness, a. good resistance to * UV, excellent resistance to high temperature (in particular, * 35 no creep up to about 120-130 C) and good flexibility at very low temperature (no breakage by folding on a mandrel of a diameter from 10 mm to -35 C). The laying of said sealing material on the support intended to receive it is carried out by gluing, textile side of the material facing the support, by means of any suitable adhesive, for example acrylic glue in aqueous dispersion or in the form of a solution in a solvent, with covering of the free edge of a sheet just placed by about 10 cm of the

  adjacent leaf being laid ..

  To improve the bonding of the adjacent sealing sheets during the aforementioned laying, a marginal zone of the textile backing layer extending along a longitudinal edge of the sealing sheet may be replaced by a thick layer. substantially equal, a thermally activatable adhesive, for example hot melt adhesive (in English "hot melt" '), the width of said zone ranging for example from 5 to 10 cm. When the cover seal is made, the connection between two adjacent sealing sheets is then made by covering the free longitudinal edge of the newly formed sealing sheet. placed by the thermally activatable adhesive zone of the textile support layer of the sealing sheet being applied, after having activated,

  by heating, the adhesive of said zone.

  According to a second embodiment of the sealing material according to the invention, the thicknesses of the layers constituting the multilayer film correspond to surface densities ranging from 30 to 300 g / m 2 for the textile backing layer, from 10 to 100 g / m2 for the foam layer and 50 to 500 g / m2 for the binder layer, said layers being arranged such that the foam layer is interposed between the textile support layer and the binder layer or that the layer of textile support

  between the foam layer and the binder layer.

  The sealing material obtained - according to the second

  embodiment can be used as sub-material

  covers (underlays), such a material having a total water tightness at a pressure of 1500 Pa and a high permeance to water vapor (at least 100 g per m and per 24 hours according to NF T 30 -018), having a good resistance to natural aging and good resistance to UV, resistant to falling objects or people and offering, if

desired, an anti-slip surface.

  The sealing sheets constituting the sub-roofing or under-roofing material are placed between the support of the tiles or slates and the frame, on the binder layer side facing the tiles or ardes, so that their longitudinal edges are substantially oriented along the line of greatest slope of the roof and that the free longitudinal edge of the newly laid sheet is covered by approximately 10 to 20 cm of the textile support layer or the layer of foam, according to the case,

adjacent leaf being laid.

  The multilayer sheet sealing material according to the invention can be manufactured by any method for producing a sheet having the characteristic three-layer structure of the invention. Advantageously, the sheet according to the invention is produced by a coating technique implemented in a conventional manner and comprising a coating of the textile support chosen by means of a precursor of the foam layer, said precursor consisting of a foaming acrylic composition. in an aqueous dispersion, a drying operation of the foam layer, then a coating, as the case may be, of the free surface of the dried foam layer or of the free surface of the layer of the textile support by means of a precursor of the binder layer, said precursor being formed of an acrylic composition in aqueous dispersion, and finally a drying of the

binder layer.

  The formation of the marginal zone of thermally activatable adhesive along a longitudinal edge of the textile support layer of the sealing wall may be achieved by abrasion of the textile layer and extrusion of the adhesive onto the fabric layer. location thus formed by abrasion of the textile. The foaming acrylic composition in aqueous dispersion, which forms the precursor of the foam layer, is prepared, in a conventional manner, by first producing an aqueous dispersion of the ingredients, namely acrylic polymeric material and various additives, chosen to constitute the composition, then subjecting said dispersion to mechanical agitation sufficient to bring

  the dispersion - in the form of a foam ..

  Similarly, the aqueous dispersion of acrylic binder, which forms the precursor of the binder layer, is produced by conventional techniques for dispersing, in an aqueous phase, the ingredients, namely acrylic polymer material and various additives, chosen to constitute the

acrylic binder.

  The various operations, namely dispersion, coating, drying, abrasion of the textile layer, extrusion of the heat-activatable adhesive, which is encountered in the manufacture of the sealing sheet, can be carried out using the various devices known to

this effect.

  The invention is illustrated by the following examples

given in a non-restrictive way.

EXAMPLE 1

  By operating by coating, two series A and B of sealing sheets were manufactured. According to the invention, they can be used

as a sub-roofing material.

  Series A: The sealing sheets of this series consisted of a non-woven sheet of polypropylene fibers with a surface mass of 110 g / m2 coated on one side with a layer of an acrylic foam based on a terpolymer

  of ethyl acrylate, acrylic acid and N-

  methylolacrylamide, said layer of foam having a basis weight of 50 g / m 2, and coated on its other surface with a layer of an acrylic binder based on a copolymer of acrylate and methyl methacrylate and loaded, as the case may be, with 2 to 5%, by weight of the binder, of glass or silicate microspheres having a diameter of about 300 μm, said

  binder layer having a basis weight of 300 g / m2.

  Series B: The sealing sheets of this series consisted of a sheet of non-woven polyester fibers having a surface density of 130 g / m2 coated on one side with an acrylic foam based on the terpolymer used to preparing the sheets of series A, said layer of foam having a basis weight of 20 g / m 2 and being in turn coated with a layer of an acrylic binder based on a copolymer of ethyl acrylate and methyl methacrylate and loaded, as the case may be, with 2 to 5%, by weight of the binder, of calcium carbonate grains having a particle size of from 200 to 500 μm, said layer of binder having a mass

surface area of 300 g / m2.

  The sealing sheets thus produced are totally watertight under a pressure of 1500 Pa and

  have a permeance to water vapor, according to NF T 30-

  018, from about 100 to 110 g per m2 and 24 hours. They also have good UV resistance and good

  fire resistance and also offer an anti-fire surface

  slips (free surface of the binder layer) satisfactory.

EXAMPLE 2

  By operating by coating, two series C and D of sealing sheets according to the invention have been manufactured which can be used

  for the realization of the waterproofness of roofs (roofing-

terraces).

  Series C: The sealing sheets of this series consisted of a sheet of non-woven polyester fibers having a surface density of 150 g / m2 coated on one side with a layer of an acrylic foam based of the terpolymer used in Example 1, said foam layer having a basis weight of 50 g / m 2 and being coated in turn with a layer of an acrylic binder based on a copolymer of butyl acrylate and of methyl methacrylate mixed with a copolymer of butyl acrylate and styrene containing 20% by weight of styrene and loaded, as the case may be, with 2 to 5%, by weight of the binder, microspheres of glass or of silicate having a diameter of about 300 μm, said binder layer having

a mass per unit area of 1700 g / m2.

  Series D: The sealing sheets of this series consisted of a nonwoven web of polypropylene fibers having a basis weight of 136 g / m 2 coated on one side with a layer of acrylic foam. base of the terpolymer used in Example 1, said. layer of foam having a basis weight of 20 g / m 2 and being coated in turn with a layer of thermo-cured acrylic binder based on a terpolymer of butyl acrylate, methyl methacrylate and N-methylolacrylamide, said layer binder having a basis weight of 1700 g / m2. Each sheet also had a hot melt adhesive coating on a 5 to 10 cm marginal area formed by abrasion of the nonwoven layer along a longitudinal edge of the sheet, this area provided with hot melt adhesive being intended to facilitate the joining of. sealing sheets

adjacent (junction lé to lé).

  C and D Series Covers are completely watertight at 0.6 MPa pressure. They also have excellent UV resistance, good creep resistance (creep temperature - greater than 120 ° C.) and good flexibility at low temperature (no breakage by folding on a 10 mm diameter mandrel). 35 C). In addition, the C-series leaves, which contain a granular filler on the surface of the binder layer, also provide a satisfactory anti-slip surface. Naturally, the invention is not limited to the embodiments described, but on the contrary it encompasses the various variants that the specialist can define by remaining

in the context of the invention.

Claims (14)

  1 - prefabricated acrylic sealing material in multilayer sheet, characterized in that said sheet comprises a layer of a textile support, a layer of a foam made of an acrylic polymeric material and a layer of a binder made of an acrylic polymer material each layer being bonded to at least one of the other two layers so that the foam layer is always in contact with the support layer textile.   2 - Material according to claim 1, characterized in that the thicknesses of the various layers of the multilayer sheet correspond to surface densities of said layers ranging from 30 to 300 g / m2 for the textile support layer, from 10 to 100 g / m2 for the layer of   foam and from 50 to 2000 g / m2 for the binder layer.   3 - Material according to claim 1 or 2, characterized in that   the textile backing layer consists of a woven or preferably non-woven web of natural or synthetic organic fibers, for example fibers made of a polymeric material such as polypropylene, polyethylene, polyamide and in particular aromatic polyamide, polyester, polymer vinylic, or fiber   inorganic, for example glass fibers.   4 - Material according to one of claims 1 to 3,   characterized in that the polymeric material used to constitute the foam layer and the polymeric material of the binder layer are each based on at least one polymer selected from homopolymers of acrylic esters, copolymers of acrylic esters between them and copolymers of one or more acrylic esters with a minor amount of one or more ethylenically unsaturated monomers such as ethylenically unsaturated carboxylic acids and their anhydrides, in particular acrylic acid, methacrylic acid, maleic anhydride, crosslinking monomers, in particular acrylamide. and methylolacrylamide,   and vinylaromatic monomers such as styrene.   Material according to Claim 4, characterized in that the acrylic esters used in the composition of the homopolymers and copolymers are chosen from alkyl acrylates and methacrylates, in which the alkyl radical is C 1 to C 18 and preferably C 2 to C 8 and may carry, optionally, a functional group,   in particular a hydroxyl or amino group.   6 - Material according to one of claims 1 to 5,   characterized in that in addition to its polymer component, each of the layers of foam and binder contain additives, especially fillers, pigments, dyes,   wetting agents, fungicides, algicides and flame retardants.   7 - Material according to one. claims 1 to -6,   characterized in that the binder layer of the multilayered sheet contains a few percent, especially 2 to%, by weight of a granular filler, for example glass or silicate microspheres, calcium carbonate, the grain size of which is approximately 150 .mu.m to 600 .mu.m to impart surface microroughness to the binder layer.   8 - Material according to one of claims 1 to 7,   characterized in that the foam layer is interposed between the textile support layer and the binder layer and in that the thicknesses of said layers correspond to surface densities of from -30 to 300 g / m 2 for the textile backing layer, from 10 to 100 g / m2 for the foam layer and from 1000 to 2000 g / m2 for the binder layer.   9 - Material according to claim 8, characterized in that the foam layer has a cellular gradient from the textile support layer to the binder layer, that is to say has a decreasing number of cells, to from the textile support layer, as one approaches the binder layer to arrive, in contact with said layer of   binding, to a continuous and closed surface.   10- material according to claim 8 or 9, characterized in that a marginal zone of the textile support layer extending along a longitudinal edge of the multilayer film is replaced by a layer of substantially equal thickness, an activatable adhesive thermally.   11- Material according to one of claims 1 to 7,   characterized in that the thicknesses of the layers constituting the multilayer film correspond to surface densities of said layers ranging from 30 to 300 g / m 2 for the textile backing layer, from 10 to 100 g / m 2 for the layer of foam and 50 to 500 g / m 2 for the binder layer, said layers being arranged in such a way that the foam layer is interposed between the textile support layer and the binder layer or that the textile support layer is arranged   between the foam layer and the binder layer.   12- Application of the material according to one of claims 1   to 11 in waterproofing of blankets or under   blankets. 13- Application according to claim 12, in. which is made waterproofing covers using the   material according to one of claims 8 to 10.   14- Application according to claim 12, in which the material according to claim 11 is used as undercladding material.