CEMENT SHEETS AND COATINGS FOR BUILDING CONSTRUCTION

Abstract

A continuous flexible cement sheet roll for coating construction slabs, is disclosed. The sheet comprising a flexible cement layer, which has a thickness of between 0.3 to 6 mm, such as between 0.5 and 5 mm, and which comprises a) essentially inorganic mortar and b) up to 15% polymeric binder. When the amount of a component in a mixture is expressed in % units, the weight % of the component relative to the weight of the whole mixture is intended. The flexible cement sheet roll of the invention comprises, a reinforcing layer of a thickness lower than the thickness of said cement layer, selected from films of a nonwoven fabrics, layers of organic or inorganic fibers, polymer webs, chop strand mat, and fiberglass mats, among others.

Claims

1. A continuous flexible cement sheet roll for coating construction slabs, the continuous flexible cement sheet roll comprising a cement layer having a thickness of between 0.5 and 5 mm and comprising inorganic mortar and up to 15% polymeric binder.

2. The flexible cement sheet roll of claim 1, further comprising a reinforcing layer of: a thickness lower than the thickness of said cement layer, selected from a film of a nonwoven fabric, a layer of organic or inorganic fibers, a polymer web, chop strand mat, and fiberglass mat.

3. The flexible cement sheet roll of claim 1, further comprising a polymeric foil which lines said cement layer.

4. The flexible cement sheet roll of claim 1, wherein said cement layer comprises i) hydraulic cement; ii) sand; iii) water; iv) polymeric binder; and v) up to 10% additives selected from thickeners, fillers, plasticizers, surfactants, dispersants, antifoams, rheology affecting agents, hydrophobicity adjusting agents, and flame retardants (FRs).

5. The flexible cement sheet roll of claim 1, wherein said cement layer comprises i) 40-70% hydraulic cement; ii) 10-25% sand; iii) up to 10% chalk or calcium carbonate; iv) 5-15% water; v) 5-15% polymeric binder; and vi) up to 5% additives selected from thickeners, fillers, plasticizers, surfactants, dispersants, antifoams, rheology affecting agents, hydrophobicity adjusting agents, and flame retardants (FRs).

6. The flexible cement sheet roll of claim 1, wherein said cement layer comprises i) 50-60% hydraulic cement of Portland types; ii) 13-23% quartz sand; iii) 5-9% chalk or calcium carbonate; iv) 8-12% water; v) 5-9% polymeric binder comprising agents selected from acrylates, styrene acrylic copolymers, styrene and butadiene copolymers, epoxy resins, methyl methacrylate, unsaturated polyester resins, polyurethane, and vinyl esters; and vi) 0.5-5% additives selected from thickeners, fillers, plasticizers, surfactants, dispersants, wetting agents, antifoams, rheology affecting agents, hydrophobicity adjusting agents, and flame retardants (FRs).

7. The flexible cement sheet roll of claim 1, further comprising a reinforcing layer comprising fiberglass embedded in said flexible cement sheet roll.

8. The flexible cement sheet roll of claim 1, further comprising a polymeric foil which lines said flexible cement sheet roll, the foil comprising a nonwoven fabric.

9. The flexible cement sheet roll of claim 1, for coating construction elements including foamed or extruded polymeric slabs, polystyrene or polyurethane panels, carton slabs, or slabs comprising mineral or organic fibers, said flexible cement sheet roll comprising a cement layer of a uniform thickness of between 1 and 4 mm, optionally a reinforcing layer embedded in said cement sheet roll, and optionally a polymeric foil lining said cement sheet roll, wherein said flexible cement sheet roll has a width of 0.2-2 m, and said flexible cement sheet roll has a length of 50-300 m.

10. A process for manufacturing a continuous flexible cement sheet roll for coating construction elements, the process comprising i) preparing a cement mortar mixture by homogenizing hydraulic cement, sand, water, 5-15% polymeric binder added to the mixture with a solvent as a fine dispersion, and up to 10% additives comprising agents selected from plasticizers, superplasticizers, antifoams, thickeners, fillers, dispersants, and viscosity adjusting agents; ii) layering said cement mortar mixture onto a heat-resistant surface of a conveyor, the surface optionally covered by a polymeric foil, thereby forming a wet cement mortar layer of a thickness of from 0.5 to 5 mm; iii) optionally embedding in said wet cement mortar layer a reinforcing layer of a thickness lower than the thickness of said wet cement mortar layer, selected from a film of a nonwoven fabric, a layer of organic or inorganic fibers, a polymer web, chop strand mat, and fiberglass mat; iv) moving said heat resistant surface, optionally with said polymeric foil, bearing said wet cement mortar mixture, optionally with said reinforcing layer, through an oven set at 110-140° C. in which said wet cement mixture sets, thereby forming a flexible solid layer; v) peeling said flexible solid layer, optionally with said polymeric foil attached to said flexible layer and lining said flexible layer, from said heat resistant surface, thereby obtaining said continuous flexible cement sheet; and vi) rolling said flexible cement sheet up, thereby obtaining a roll of readymade continuous separate cement sheet for immediate or future use in coating construction elements, wherein the continuous sheet is strong and flexible enough to be unfolded and glued on at least one surface of said construction elements, the elements including foamed or extruded slabs, polystyrene or polyurethane panels, carton slabs, slabs comprising mineral or organic fibers, and metal columns or beams.

11. The process of claim 10, further comprising i) preparing said homogeneous cement mortar mixture by mixing 35-60% hydraulic cement, 8-20% quartz sand, up to 8% of chalk or calcium carbonate, 15-30% water, 5-15% polymeric binder added to the mixture as a concentrated fine dispersion, and up to 4% additives comprising agents selected from plasticizers, superplasticizers, antifoams, thickeners, fillers, dispersants, surfactants, dispersants, rheology affecting agents, hydrophobicity adjusting agents, FRs, dioctylphthalate, aluminum hydroxide, magnesium hydroxide, cellulose, nylon, fume silica, perlite, vermiculite, glass, PP, basalt, preservatives, and dyes; ii) layering said cement mortar mixture onto said heat-resistant surface, the surface comprising a Teflon surface of a belt conveyor 0.2-2 m wide, optionally covered with said polymeric foil; iii) optionally embedding said reinforcing layer in said wet cement mortar layer, the reinforcing layer comprising fiberglass; iv) moving said heat resistant surface bearing said wet cement mixture optionally with said reinforcing layer into an oven set at 120-130° C., in which said wet cement mortar mixture sets to form said flexible solid layer; v) peeling said layer from said foil, optionally together with said polymeric foil which becomes an integral part of the produced flexible sheet, thereby obtaining said continuous flexible cement sheet; vi) rolling said flexible sheet up, thereby obtaining a roll of continuous cement sheet having a length of 20-200 m for immediate use or for storing for a future use; the continuous sheet being enough strong and flexible to be unfolded and glued onto the surface of said construction elements, including foamed and extruded slabs, polystyrene or polyurethane panels, carton slabs, slabs comprising mineral or organic fibers, and metal columns or beams.

12. The process of claim 10, wherein said step iv) is performed in a continuous manner or in a batch manner.

13. The process of claim 10, wherein said polymeric foil is selected from nonwoven fabric webs.

14. A process for manufacturing a construction composite panel comprising a polymer slab core and a cement coat at least on one side of the slab, the process comprising: i) preparing a cement mortar mixture by homogenizing hydraulic cement, sand, water, 5-15% polymeric binder added to the mixture as a fine dispersion, and up to 10% additives comprising agents selected from plasticizers, superplasticizers, antifoams, thickeners, fillers, dispersants, and viscosity adjusting agents; ii) casting said cement mortar mixture onto a heat-resistant surface of a conveyor, the surface optionally covered by a polymeric foil, thereby forming a wet cement mortar layer of a thickness of from 0.5 to 5 mm; iii) optionally embedding a reinforcing layer of a thickness lower than the thickness of said wet cement mortar layer, selected from a film of a nonwoven fabric, a layer of organic or inorganic fibers, a polymer web, chop strand mat, and fiberglass mat, in said wet cement mortar layer; iv) setting cement mortar layer by exposing it to a temperature of 110-140° C., in a continuous or in a batch manner, thereby providing a solid and flexible cement layer; v) peeling said flexible cement layer, optionally with said polymeric foil, thereby obtaining a continuous flexible cement sheet; vi) folding the sheet to provide a roll of separate readymade flexible cement sheet; vii) applying glue on one side of said slab core or on one side of said flexible cement sheet after unfolding from the coil, and pressing said cement sheet onto said core, thereby obtaining a composite panel coated on one side; viii) optionally gluing said flexible cement sheet on the second side of said slab, thereby obtaining a sandwich building composite panel; and ix) clearing and cutting the coated slab to desired shape and size; thereby obtaining structure elements coated on one or two sides, including sandwich-structured polystyrene panels coated on both sides.

15-44. (canceled)

45. A structural element comprising a polystyrene panel coated on one or both sides by the flexible cement sheet roll of claim 1.

46. A structural element comprising a polystyrene panel coated on one or both sides by the flexible cement sheet roll of claim 4.

47. A structural element comprising a polystyrene panel coated on one or both sides by the flexible cement sheet roll of claim 5.

48. A structural element comprising a polystyrene panel coated on one or both sides by the flexible cement sheet roll of claim 6.

Description

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0043] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the present invention.

[0044] It has now been found that the cement-coated polystyrene (PS) slabs can be manufactured in a simple and environmental friendly process, doing with less working space and less complex manufacturing equipment than the known processes, while providing cost-effective products of any desired dimensions. The process of the invention precludes the problems with moving the panel to be coated to the sites of the coating activities, problems with premature or delayed setting of the formed cement slurry, problems with uneven deposition of the slurry on the slabs, and difficulties about the maintenance of cement delivering equipment and about clogging.

[0045] The invention preferably provides PS panels coated with a cement layer, either made of expanded polystyrene (EPS) or extruded polystyrene (XPS), either coated on one side or on two sides. The continual flexible cement sheet may be advantageously employed for coating other polymer slabs and even other building elements. The method of the invention avoids cumbersome steps of existing methods, such as transporting PS or other slabs through coating machines whereby forming a cement layer on one side of the slab, embedding fiberglass within said layer on the slab, sawing the slab with a layer in desired pieces, and repeating the coating on the other side of the slab. The method of the invention provides a cement layer entirely separate from the slab and combines the separate cement layer with the slab when the layer is not wet any more. Moreover, the separate cement layer is flexible and well workable, so that it can be rolled up to provide rolls of a separate readymade cement layer to be glued onto PS slabs anytime and anywhere needed.

[0046] The separate cement layer sheet according to the invention is prepared from a mixture comprising 15-70% cement, 5-30% polymerizable or polymerized latex dispersion, 5-25% sand, up to 10% chalk or lime or calcium carbonate, 10-35% water, and additives comprising agents selected from thickeners, fillers, plasticizers, surfactants, dispersants, antifoams, rheology affecting agents, wetting agents, hydrophobicity adjusting agents, flame retardants (FRs), and others. Percent values relate to weight percent throughout. In some embodiments, the latex emulsion comprises styrene-butadiene (SB). In some embodiments, the additives comprise plasticizers like dioctylphthalate. In some embodiments, the FR comprise aluminum hydroxide or magnesium hydroxide. In some embodiments, the fillers comprise polymers like cellulose or nylon. In some embodiments, the fillers comprise fume silica or perlite.

[0047] The wet mixture for producing the cement layer may comprise, in some embodiments, 30-70% cement, 5-20% latex dispersion, 5-25% quartz sand, 2-10% chalk or calcium carbonate, 5-30% water, 0.5-10% total additives; the amount of dry polymer binder in the mixture may be 2-15%, such as 3-10%; the total amount of water in the mixture may be 7-45%, such as 8-35%. In some embodiment, said mortar-like wet mixture for producing the flexible cement layer may comprise, 40-60% cement, 10-20% latex emulsion, 10-25% quartz sand, up to 10 chalk or calcium carbonate, 10-20% water, 0.5-1% superplasticizer, and antifoam, thickener, filler, dispersant, surfactant, viscosity adjusting agent, each one in an amount between 0.1 to 1.0%; the amount of dry polymer binder in the mixture may be 4-12%, such as 5-10%; the total amount of water in the mixture may be 15-35%, such as 20-30%. The wet mixture for producing the cement layer may for example comprise 40-60% cement, 10-16% latex dispersion, 10-22% quartz sand, 4-9% chalk, 5-25% water, and 0.8-4% total additives, while the amount of dry polymer binder may be 5-8%, and the total amount of water in the mixture may be 15-32.

[0048] Said viscosity adjusting agents may comprise rheological agents such as cellulose to bind water. Said latex dispersion may comprise polymer or polymerizable components. A part of the cement or sand in the wet mortar mixture may be replaced with calcium oxide or calcium hydroxide or plaster or calcium sulfate. Water reducing agents may be added, and surfactants to improve workability. If lighter sheet is desired, a component selected from perlite, vermiculite, fume silica, and hollow sand or other light filler may be added. When a flame retardant is desired, aluminum hydroxide or magnesium hydroxide may be added. Hydrophobic agents may be added. For increasing flexibility, dioctylphthalate (DOP) or similar agents may be added. In order to prevent cracks, fibers may be added, such as nylon, glass, PP, basalt, and others. Other additives or fillers compatible with the coating may be employed.

[0049] An advantageous aspect of the technology according to the invention is providing a cement layer separately, which facilitates the process and enables to produce thinner panels. Said cement layer, comprising components as described above, is layered, for example by spraying, onto a polymeric surface to bear it to an oven, the surface comprising for example a Teflon coating on a conveyor belt which is a part of the manufacturing equipment, comprising nonwoven textile, such as polyester foil, or PET, placed on the conveyor belt, possibly becoming an integral part of the final, dry, flexible cement layer. In one preferred embodiment, fiberglass is inserted in the wet cement layer, the layer moving to an oven heated to 120-130° C. The wet cement mixture undergoes setting when exposed to said high temperature, providing a solid and firm but flexible cement sheet, which is then peeled from the polymer foil and rolled up on a reel. The peeling step may be combined with the coating step in a continuous process; in a preferred embodiment, the peeled flexible cement sheet is rolled up for storage, marketing, and transport. The desired product is preferably a reel or roll of a flexible cement layer for use in coating foamed polymer core, either on one side or on both side of the core slab. In some embodiments, the sheet is wound on a reel core; in other embodiments, the wound sheet is densely rolled up for storage and transport without any core. Preferably, the slab comprises PS slabs, and the process of the invention provides composite building panels comprising either PS coated with said flexible cement sheet on one side, or sandwich panels comprising PS slab coated on both sides.

[0050] One of the advantageous features of the invention is providing a separate flexible cement sheet, readymade for future use in coating foamed slabs to provide building panels. In a preferred embodiment, the flexible cement sheet prepared for coating slabs, such as foamed polymer slabs like PS or PU slabs, is rolled up on rolls stable and ready for any future use, the flexible cement sheet usually having a thickness of 0.3-6 mm, preferably 0.5-5 mm, such as 1-4 mm, for example 2-3 mm, and being rolled as sheets for example 20-200 cm wide, and 50-300 m long, the rolls having the form of cylinders of a diameter usually between 0.2 and 1 m.

[0051] The invention provides a process for manufacturing composite panels comprising foamed slabs coated with a cement layer, comprising a step of gluing the readymade cement sheet of the invention as above described onto foamed polymer slabs. The slabs are combined with the cement sheet on one or both sides while employing glue between the foamed polymer and the cement sheet. The invention provides composite building panels, preferably in a continuous process comprising steps of spreading glue on the surface of the foamed slab or flexible cement sheet, combining the slab and the sheet, and cutting the composite panels to the desired size and packaging.

[0052] A cement layer for coating construction slabs, such as polystyrene panels, readymade and separately pre-prepared for future use, for example as a 1-4 mm thick sheet of flexible cement layer reeled on a roll, for example 1 mm×30 cm×150 m; the layer may be cast, eventually comprising a fiberglass net, on a Teflon© conveyor belt, optionally covered with a polyester foil or glass fiber mat or other nonwoven web, to become an integral part of the peeled and rolled up flexible layer, to be placed in an oven at 120-130° C., and then peeled from the plastic base and rolled.

[0053] In one embodiment, the process for manufacturing the flexible sheet of the invention comprises coating said cement composition onto a thin polymer film, such as a textile layer, such as polyester, or onto a conveyor surface which is a part of the manufacturing device preferably comprising a Teflon layer, optionally covered with a nonwoven textile. The polymer surface bears the wet cement layer after its forming to an oven, the layer usually being from 0.5 to 5 mm high; a fiberglass comprising foil or mat or web is preferably sunk into the wet cement layer. The wet layer on said polymer surface which is heat resistant moves to the oven set at 120-130□ C., and after solidifying, the essentially dry flexible cement sheet is peeled off the underlying conveyor surface and is rolled up in the end of the production line. In one embodiment, the peeling step is performed in a peeling device. The cement layer may be layered onto a nonwoven textile or a fiber carpet which becomes an integral part of the produced cement sheet. Provided is a flexible cement sheet, optionally with a fiberglass-comprising film inside, the sheet being rolled up. The wet cement may be layered onto a foil which will become an integral part of the sheet, providing a flexible cement sheet with or without fiberglass inside, covered on the bottom with a nonwoven fabric, for example chop strand mat.

[0054] The process of manufacturing composite building panels according to the invention comprises i) providing rolls of a firm flexible cement sheet, for example 0.5-5 mm thick, for example 50-100 cm wide, and 100-200 m long, ii) gluing either one side of the sheet or one side of a building slab, iii) combining said sheet and said slab with the glue joining them to provide a composite panel for building; iv) cutting the composite panel to desired size; and v) optionally combining the second side of the slab with the sheet by said glue. In one embodiment, said glue is spread onto the surface of the cement flexible sheet and a panel is put onto it. If both panel sides are to be coated, its other side is covered with the glue and the flexible cement sheet is put onto it. The panel such as PS panel may move over the flexible cement sheet unfolded from a roll and covered with glue, the panel is pushed by its bottom side onto the glued surface of the flexible sheet, and one-side coated panel continues to move while being covered with glue on its upper side, while flexible sheet form another unfolding roll is pushed onto the panel upper side, followed by cutting and smoothening the edges of the sandwich panel by cutting means like saws or knives and by smoothening means, after which the sandwich panel is divide into parts of desired sizes, while removing residues and packaging the final composite building panels.

[0055] The invention thus provides a special product, process, and system comprising a roll of flexible cement sheet which is formed by a) casting inorganic mortar mixed with polymeric latex onto a heat resistant solid surface optionally covered with a polymeric foil, b) setting the cement, c) peeling the solidified cement, optionally with the foil, from said solid surface, and rolling it up for later use, which comprises d) unfolding and gluing said separate readymade rolled sheet onto construction slabs such as PS panels.

[0056] This invention relates to a process for producing composite building panels comprising cement-coated slabs, wherein a slurry of mortar and polymeric latex is cast on a solid surface, optionally covered with a polymer foil, and then it is set at a higher temperature to provide a flexible cement sheet, which is separated from said solid surface, in one embodiment together with the attached foil, and rolled up to be stored as rolls for future use. In a preferred embodiment, the cement sheet is reinforced by embedding into it a fiberglass mat or mesh, which may be unfolded before embedding from a roll. The composite panels exhibit high strength.

[0057] The process may employ a feed means for depositing the wet cement mixture upon said polymer foil or web. The mixture has a consistency of slurry or paste, which is uniformly spread onto the surface of a foil or a conveyor in a uniform layer, said foil and conveyor preferably moving like an endless tape having the desired width, such as 50-100 cm. The means may include a metering nozzle having a width slightly less than the width of said tape, and a spreading means providing a thin layer uniformly distributed on the tape, exhibiting a predetermined thickness, such as between 0.5 and 5 mm, for example 1-3 mm. The invention relates to a process providing composite building panels for an indoor or outdoor use, preferably in a continuous manner.

[0058] The invention provides a system for manufacturing slabs of foamed or extruded polymer coated on at least one side with a readymade flexible cement sheet, the sheet comprising inorganic materials, including hydraulic cement, sand, chalk, and additives, and a polymeric binder, preferably incorporated in the form of a latex, such as styrene-butadiene latex.

[0059] Cements are usually brittle, but the cement mixture of the invention is enough elastic to be rolled to form rolls to be stored, and used either immediately in a process of making composite panels, or preferably for future use. The cementitious material and the polymeric component are homogeneously combined to provide a solid sheet which, however, is enough strong and flexible to be bent and even rolled. The cement is prepared from a mixture comprising inorganic, preferably pozzolanic materials, and organic polymers, with additives ensuring strength and flexibility, including superplasticizer additives. After homogenizing, the shapeable, mortar-like mixture is extruded or poured onto a solid surface, optionally covered with a polymeric foil while adjusting the uniform thickness of the obtained layer, comprising extrusion, troweling, calendaring, rolling, etc. Usually, the process of mortar or cement preparation is quite complex, needs specific material ratios and takes up space and time, and may be cumbersome and messy; therefore, such process may extremely complicate production of mortar/cement coated slabs. The invention separates the process of producing the wet cement mortar and the process of coating the building slabs, while addressing most of the problems known in the field.

[0060] The invention will be further described and illustrated by the following examples.

EXAMPLES

Example 1

[0061] A wet cement mixture was prepared by homogenizing the following components (in weight percent): 51% Portland cement, 13% water, 13% quartz sand, 6.5% chalk, 13% binder latex purchased from EOC Belgium (styrene-butadiene emulsion L 6066, 48% solids), 0.25% antifoam, 0.25% thickener, 0.25% dispersant, 0.8% dioctylphthalate as superplasticizer, 0.9% perlite, and 0.4% wetting agent. The mixture was spread on a nonwoven polyester foil (PE) band to form a layer 2 mm thick, a fiberglass based web of the width about 1 mm was pushed into the wet mixture layer, the foil with the cement layer and fiberglass was placed in an oven at 125° C. for 8 minutes. A flexible cement layer was obtained, being enough strong to be peeled from the PE foil and enough flexible to be rolled without forming cracks.

Example 2

[0062] A wet cement mixture was prepared by homogenizing the following components (in weight percent): 46% Portland cement, 19% water, 17% quartz sand, 5% chalk, 12% binder latex (styrene-acrylic copolymer emulsion), 0.2% antifoam, 0.2% thickener (cellulose), 0.2 superplasticizer, and 0.2% wetting agent. The mixture was spread on a nonwoven polyester foil (PE) band to form a layer 3 mm thick, a fiberglass based web of the width about 1 mm was pushed into the wet mixture layer, the foil with the cement layer and fiberglass was placed in an oven at 125° C. for 12 minutes. A flexible cement layer was obtained, enough firm and flexible to be peeled from the PE foil and rolled.

Example 3

[0063] Glue was spread on a one side of a polystyrene (PS) slab 1 m×1 m, 0.8 cm thick, and two flexible cement sheet pieces, 50 cm×1 m, obtained according to Example 1, were pushed on the glue to cover one side of the PS slab to obtain a composite panel. The other side was glued and coated with the same flexible cement bands as the first side. The sandwich panel exhibited desired strength.

[0064] Some additional aspects of the invention may be related to intumescent layers. It has now been found that slabs or panels used in building construction can be provided with intumescent layers simply without employing intumescent components or wet raw materials, in a simple, health-friendly and environmentally friendly process, using readymade separate solid intumescent sheet, in any stage of the slabs production or installation. The system of the invention does with less working space and less complex manufacturing equipment than the known processes, while providing cost-effective results. The process of the invention precludes the problems with manipulating intumescent raw materials and with ungainly operation steps of applying the materials on the construction site, as well as problems with uneven deposition of the intumescent layer and difficulties about the maintenance of the equipment for delivery of intumescent slurries.

[0065] The invention provides a readymade separate intumescent sheet for simply coating any building construction element, comprising i) preparing a wet intumescent mixture by homogenizing components, such as for example ammonium polyphosphate, a polyol, a spumific agent, and additives selected from solvents, latexes, polymeric dispersions or emulsions, viscosity adjusters, dispersants, antifoams, surfactants, fillers, flexibility enhancers, preservatives, plasticizers, synergists, and dyes; ii) layering said mixture onto a reinforcing mat, the mat comprising materials selected from layers of organic or inorganic fibers, polymer webs, polymer films, chop strand mat, nonwoven fabrics, and fiberglass mat to form a layer of a thickness of about 0.5 to 5 mm; iii) optionally embedding in said wet layer another web or mat or foil; iv) moving said wet layer through an oven and drying said layer; and optionally v) attaching to the dried sheet, or lining said dried sheet with, another thin layer, either to finalize the mechanical or chemical properties of the sheet or to provide the sheet with an adhesive layer to be employed when attaching the sheet on the surface to be protected; thereby obtaining said intumescent sheet as a separate and readymade intumescent sheet to be immediately used or preferably stored for any future use.

[0066] In some embodiments, the additives may include agents simplifying the manufacturing process or improving the properties of the intumescent sheet, the former comprising for example dispersants or viscosity adjusters, the latter comprising for example flame-retarding adjusters or flexibility adjusters. Said synergists may include silicates, phyllosilicates, clays, fumes silica, vermiculite, metal oxides, and other known synergists. Of course, other known intumescent mixtures may be employed, for example comprising commercial pre-prepared mixtures, emulsions, and other combinations, usable as paste or spray or paint. The sheet for coating the surface of the construction elements may be a planar sheet of desired dimensions to be glued onto the surface of the same dimensions. The sheet is preferably a continuous flexible sheet, and the system and the process of the invention comprise a step of folding and rolling up said continuous flexible sheet to rolls for storage and future use, as well as a step of unfolding and gluing the sheet onto the surface. The process of the invention may provide planar sheets, or rolls of continuous sheet, of any desired and required dimensions.

[0067] One of the advantageous features of the invention is providing a separate flexible intumescent sheet, readymade for future use in coating building panels, walls, ceilings, beams, and columns. The coating may be performed on construction site or during the manufacture of the building elements. In a preferred embodiment, the flexible intumescent sheet is rolled up on rolls stable and ready for storage, transport and any future use, the sheet usually having a thickness of 0.5-5 mm, and being rolled as sheets for example 0.1-4 m wide, usually 0.2-3 m wide, such as 0.2-2 m wide, and up to 500 m long, such as 30-300 m long, for example 1 m wide and 100 m long.

[0068] The invention provides a process for manufacturing composite panels comprising slabs coated with one or two intumescent layers, comprising a step of gluing the readymade sheet of the invention onto the slabs. The slabs are combined with the sheet on one or both sides while employing glue between the polymer and the sheet, or other attaching means, including mechanical means. The invention provides, in one aspect, composite building panels, preferably in a continuous process comprising steps of spreading glue on the surface of the slab or the sheet and combining the slab and sheet, and cutting the composite panels to the desired size and packaging. The composite panels may comprise cement boards, plaster boards, gypsum boards and pa The invention thus provides a special product, process, and system, comprising a roll of flexible intumescent sheet which is formed by a) casting wet intumescent mixture with additives onto a reinforcing mat, b) drying, and c) rolling up the sheet by itself or on reels; the invention further provides a special process and system, comprising a step of unfolding the roll and attaching the readymade sheet onto building slabs or other surfaces including ceilings and walls, as well as columns and beams. The readymade intumescent sheet of the invention is advantageously employed for easy and cost-effective preparation of building surfaces coated with intumescent layer, the surfaces including cement boards, plaster boards, gypsum boards and gypsum panels. The process of the invention may comprise the step of attaching the intumescent sheet on the solid surface, or employing the readymade intumescent sheet as a base onto which additional construction layers are formed. In one embodiment, a wet mixture comprising cement, plaster materials or gypsum is layered on the readymade sheet, and the obtained slab is further processes by adding further layers or sheets or components. The system of the invention provides building construction elements provided with intumescent coating, including beams or columns; walls or ceilings; cladding for walls and ceilings; panels and slabs comprising metals, polymers, cartons, cements and plasters; cement boards, plaster boards, and gypsum boards.

[0069] Intumescent coatings can be usually formed from materials available in the market, such as in the form of paints or pastes for protecting the construction base from the heat of flame. The intumescent materials are applied as a thin layer by spreading or spraying on the surface of the construction elements. The exposure to fire makes the layer swell by creating a foam which insulates and protects the base, such as steel beams and columns. For example, steel starts to lose its strength at 300° C., and substantially at 500° C., and the intumescent coating may slower the temperature rise inside the steel construction and thus prevent or delay its collapse. The application of raw material mixtures onto large surfaces of the construction elements in situ is complicated, and the readymade sheet of the invention will immensely simplify the process. The invention provides a readymade intumescent flexible sheet having a thickness of 0.5 to 5 mm rolled up in cylinder rolls, to be applied and attached onto the surface of the construction elements to be protected from flame in accordance with the regulations. For example, the incorporation of the anti-flame protection into plaster panels nowadays requires substantial modification in their production process; the use of the sheet according to the invention will simplify the whole procedure. The intumescent sheet of the invention may be manufactured in a process comprising steps of i) creating a layer of an intumescent mixture on an reinforcing mat, wherein the mat may be placed on a carrier foil such as comprising PE, PP, PET, or other materials, ii) moving the mat and the layer through an oven and drying, and iii) rolling the dried layer and mat up to cylinder rolls of readymade flexible intumescent sheet to be applied anytime and anywhere else, wherein said dried layer and mat are peeled from the carrier foil when present before rolling up. The process may comprise a lining the sheet with an adhesive layer, optionally protected, for example with silicon-comprising paper.

[0070] The invention will be further described and illustrated by the following examples:

Additional Example

Example 4

[0071] An intumescent wet mixture was prepared by homogenizing 29% ammonium polyphosphate, 22% binder emulsion (vinyl acetate based copolymer), 12% pentaerythritol, 14% melamine, 10% titanium oxide, 6.6% water, 5% kaolin, 0.5% fibers, 0.3% preservative, 0.2% surfactant, 0.2% wetting agent, and 0.2% antifoam. The mixture was spread on a fiberglass mat to form a layer 2 mm thick, and the wet sheet was dried at a temperature of 110° C. A flexible intumescent sheet was obtained, which could be folded and rolled up without cracks in the intumescent layer.

[0072] According to additional aspects of the invention it has now been found that slabs or panels used in building construction can be provided with thermo-insulating layers simply without employing thermo-insulating components or wet raw materials, in a simple, health-friendly and environmentally friendly process, using readymade separate solid thermo-insulating sheet, in any stage of the slabs production or installation. The system of the invention does with less working space and less complex manufacturing equipment than the known processes, while providing cost-effective results. The process of the invention precludes the problems with manipulating thermo-insulating raw materials and with ungainly operation steps of applying the materials on the construction site, as well as problems with uneven deposition of the thermo-insulating layer and difficulties about the maintenance of the equipment for delivery of thermo-insulating suspensions or slurries.

[0073] The invention provides a readymade separate thermo-insulating sheet for simply coating any building construction element, comprising i) preparing a wet thermo-insulating mixture by homogenizing the required components, comprising solvents, polymeric latexes, and additives, selected from viscosity adjusters, dispersants, antifoams, surfactants, fillers, flexibility enhancers, preservatives, plasticizers, synergists, and dyes; ii) layering said mixture onto a reinforcing mat, the mat comprising materials selected from layers of organic or inorganic fibers, polymer webs, polymer films, chop strand mat, nonwoven fabrics, and fiberglass mat to form a layer of a thickness of about 0.2 to 4 mm; iii) optionally embedding in said wet layer another web or mat or foil; iv) moving said wet layer through an oven and drying said layer; and optionally v) attaching to the dried sheet, or lining said dried sheet with, another thin layer, either to finalize the mechanical or chemical properties of the sheet or to provide the sheet with an adhesive layer to be employed when attaching the sheet on the surface to be protected; thereby obtaining said thermo-insulating sheet as a separate and readymade thermo-insulating sheet to be immediately used or preferably stored for any future use. Said additives may include agents simplifying the manufacturing process or improving the properties of the thermo-insulating sheet, the former comprising for example dispersants or viscosity adjusters, the latter comprising for example flexibility adjusters. The wet thermo-insulating mixture may comprise silicates, phyllosilicates, clays, fumes silica, vermiculite, metal oxides, and other metal oxides. Of course, commercial pre-prepared mixtures, emulsions, and other combinations, usable as paste or spray or paint, may be included. The sheet for coating the surface of the construction elements may be a planar sheet of desired dimensions to be glued onto the surface of the same dimensions. The sheet is preferably a continuous flexible sheet, and the system and the process of the invention comprise a step of folding and rolling up said continuous flexible sheet to rolls for storage and future use, as well as a step of unfolding and gluing the sheet onto the surface. The process of the invention may provide planar sheets, or rolls of continuous sheet, of any desired and required dimensions.

[0074] One of the advantageous features of the invention is providing a separate flexible thermo-insulating sheet, readymade for future use in coating building panels, walls, ceilings, beams, and columns. The coating may be performed on construction site or during the manufacture of the building elements. In a preferred embodiment, the flexible thermo-insulating sheet is rolled up on rolls stable and ready for storage, transport and any future use, the sheet usually having a thickness of 0.2-4 mm, and being rolled as sheets for example 0.1-4 m wide, usually 0.2-3 m wide, such as 0.2-2 m wide, and up to 500 m long, such as 30-300 m long, for example 1 m wide and 100 m long.

[0075] The invention provides a process for manufacturing composite panels comprising slabs coated with one or two thermo-insulating layers, comprising a step of gluing the readymade sheet of the invention onto the slabs. The slabs are combined with the sheet on one or both sides while employing glue between the polymer and the sheet, or other attaching means, including mechanical means. The invention provides, in one aspect, composite building panels, preferably in a continuous process comprising steps of spreading glue on the surface of the slab or the sheet and combining the slab and sheet, and cutting the composite panels to the desired size and packaging. The composite panels may comprise cement boards, plaster boards, gypsum boards and panels.

[0076] mixture with additives onto a reinforcing mat, b) drying, and c) rolling up the sheet by itself or on reels; the invention further provides an advantageous novel process and system, comprising a step of unfolding the roll and attaching the readymade sheet onto building slabs or other surfaces including ceilings and walls, as well as columns and beams. The readymade thermo-insulating sheet of the invention is advantageously employed for easy and cost-effective preparation of building surfaces coated with thermo-insulating layer, the surfaces including cement boards, plaster boards, gypsum boards and gypsum panels. The process of the invention may comprise the step of attaching the thermo-insulating sheet on the solid surface, or employing the readymade thermo-insulating sheet as a base onto which additional construction layers are formed.

[0077] In one embodiment, a wet mixture comprising cement, plaster materials or gypsum is layered on the readymade sheet, and the obtained slab is further processes by adding further layers or sheets or components. The system of the invention provides building construction elements provided with thermo-insulating coating, including beams or columns; walls or ceilings; cladding for walls and ceilings; panels and slabs comprising metals, polymers, cartons, cements and plasters; cement boards, plaster boards, and gypsum boards.

[0078] Thermo-insulating coatings of the invention can be formed from known components exhibiting thermal protecting effects or from readymade mixtures available in the market, such as in the form of paints or pastes for protecting the construction base from heat. However, the application of raw material mixtures onto large surfaces of the construction elements in situ according to known methods is complicated, and the readymade sheet of the invention will immensely simplify the process. The invention provides a readymade thermo-insulating flexible sheet having a thickness of 0.2 to 4 mm rolled up in cylinder rolls, to be applied and attached onto the surface of the construction elements to be protected from flame in accordance with the regulations.

[0079] For example, the incorporation of the anti-flame protection into plaster panels nowadays requires substantial modification in their production process; the use of the sheet according to the invention will simplify the whole procedure. The thermo-insulating sheet of the invention may be manufactured in a process comprising steps of i) creating a layer of a thermo-insulating mixture on an reinforcing mat, wherein the mat may be placed on a carrier foil such as comprising PE, PP, PET, or other materials, ii) moving the mat and the layer through an oven and drying, and iii) rolling the dried layer and mat up to cylinder rolls of readymade flexible thermo-insulating sheet to be applied anytime and anywhere else, wherein said dried layer and mat are peeled from the carrier foil when present before rolling up. The process may comprise a lining the sheet with an adhesive layer, optionally protected, for example with silicon-comprising paper.

[0080] The thermo-insulating mixture for use according to the invention usually comprises dried polymeric latex, often acrylic based. An acrylic elastomeric emulsion is employed in preparing wet mixtures for making the sheet of the invention, containing nano-sized particles, preferably comprising beside polymeric latex particles, usually dispersed in water, also inorganic particles such as metal oxides, commercially available or produced by ultrasonicating a suspension of metal oxides and water. The nanoparticles may comprise titanium oxide, silicon oxide, zinc oxide, and others. Other special materials known in the art may be employed in the preparation of the wet mixture for manufacturing the thermo-insulating sheet of the invention, including, for example, hollow glass microspheres, sepiolite nanofibers, and others.

[0081] The particles block heat transfer in the final dried layer, reflect thermal radiation, and preferably also create a moisture barrier. The final protecting layer, preferably white, exhibits good thermal radiation reflectance and heat transfer resistance (heat transfer resistance is he reciprocal of heat conductance). The sheet of the invention usually exhibits thermal reflectance, in the infrared region of light of between 700-2200 nm, of 70% or more, for example 80% or more, such as 85% or more, such as 90% or more, such as 92% or more, such as 94% or more. Thermal insulating effect of a thermo-insulating sheet of the invention can be checked by thermography, for example by heating board samples from backside with infrared lamp and comparing changes of temperature at the front side; the highest reached temperature at the front side may be lower by at least 3° C., such as at least 5° C., for the board coated with the sheet of the invention, compared to the board sample of the same dimensions without the sheet. Thermal conductivity of a board sample or model panel coated with the sheet of the invention is lower than a panel of the same dimensions without the sheet, the difference may be at least 0.2 W.Math.K.sup.−1m.sup.−2, such as at least 0.3 W.Math.K.sup.−1m.sup.−2, such as at least 0.4 W.Math.K.sup.−1m.sup.−2, such as at least 0.5 W.Math.K.sup.−1m.sup.−2.

[0082] The sheet of the invention creates a thermal blanket on the surface of the building construction elements which, moreover, is resistant to water, as well as to fungi and algae. The dry heat-insulating layer on the sheet of the invention is enough flexible to be rolled up, and maintains its elasticity over a wide range of temperature changes, thereby ensuring the needed robustness and long-term effects.

[0083] The effects of radiation and conduction, contributing most to the heat transfer in buildings, are both reduced by the sheet of the invention; the sheet exhibits enhanced reflectivity, thereby bouncing back the incoming radiation, and reduced heat conductivity, thereby blocking the heat transfer between the exterior and interior of the building.

[0084] The thermo-insulating sheet of the invention is advantageously employed for coating external surfaces, internal surfaces, walls, ceilings, masonry, concrete, cement plates, plaster board, building panels, as well as any building construction elements, thereby slowing down the heat transfer, for example from inside to outside when heating in the winter or from outside to inside when cooling in the summer. The treated surfaces may include horizontal and vertical surfaces as well, the surfaces comprising concrete, cement, mortar, asphalt, but also metals, plastics, cellulosic materials or wood.

[0085] The method according to the invention for producing the thermo-insulating sheet employs a wet mixture for making the final dry thermo-insulating layer, which wet mixture may comprise commercially available thermal insulating materials, including paints, examples including products of company NanoPhos SA or NanoSilv S.r.l.

[0086] The method and system of the invention for reducing the thermal conductance of the building elements enable to avoid complexities of wet paint application, to obviate weather interferences, to prevent contaminations of the working space with wet paint, and to preclude waiting for paint drying/ curing/ stabilization which may take hours or days.

[0087] The invention will be further described and illustrated by the following example.

Example 5

[0088] SurfaPaint ThermoDry of NanoPhos was sprayed onto a fiberglass mat to form a layer of 1 mm thick, and the wet sheet was dried at a temperature of 120° C. A flexible thermo-insulating sheet was obtained, which could be folded and rolled up without cracks in the thermo-insulating layer.

[0089] While certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will now occur to those of ordinary skill in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.