WO2011060684A1

WO2011060684A1 - Integrated panel for exterior thermal insulation finish systems

Info

Publication number: WO2011060684A1
Application number: PCT/CN2010/078256
Authority: WO
Inventors: Liang Zhang; Hari Parvatareddy; Loganathan Ravisanker; Mei Qun Wu
Original assignee: Dow Global Technologies Inc.
Priority date: 2009-11-20
Filing date: 2010-10-29
Publication date: 2011-05-26
Also published as: WO2011060684A8

Abstract

An integrated panel for exterior thermal insulation finish systems comprises a thermal insulation layer (1) and a multifunctional facing layer (2) applied on a surface of the thermal insulation layer (1), wherein the multifunctional facing layer (2) comprises a multifunction facing composition comprising a multi-hydraulic binder composition that comprises at least one accelerating binder and polymer emulsion or polymer powders. A method of making the integrated panel is also provided.

Description

INTEGRATED PANEL FOR EXTERIOR INSULATION

FINISH SYSTEMS

BACKGROUND OF THE INVENTION Field o f the Invention The present invention relates to exterior thermal insulation system in construction industry. Particularly, the present invention relates to a prefabricated panel which integrates decoration and thermal insulation layers.

Discussion of Background Information

External Insulation Finish Systems (EIFS), which were developed in Europe in the early 1970s, are an important application for energy savings in the building industry. The function of EIFS is to stabilize indoor temperature and humidity during changes in climatic conditions to improve comfort in a residence or other building. Energy is saved through the application of insulation materials in this system. In addition, the reductions in temperature shift and moisture condensation of external wall reduce aging and damage of the buildings.

EIFS mainly have the following components: insulation board, adhesive (for adhering insulation board to a wall), basecoat mortar (protective coat for insulation board and base coat of finish material) and decorating materials (painting, tile and stucco, etc.). In the 1970s, EIFS adhesive mortar and basecoat mortar were made by mixing liquid emulsion adhesive into cement at the construction site, which was later developed into the two-component formulation used by the industry currently.

CN2620741Y provides a panel consisting of an insulation board made of XPS or PU foam, an interface adhesive, a high strength skim coat, a decorative coating layer such as fluorocarbon metallic paint, polyurethane metallic paint or colorful paint, wherein said interface adhesive is made of acrylic emulsion, 625#cement (a cement grade in China, which means an cement with a compressive strength of greater than 625 kilogram per square centimeter (hereinafter "kg/cm²") at 28 days under specified proportion and conditions) and METHOCEL™ brand cellulose ether (METHOCEL is a trademark of The Dow Chemical Company); said high strength skim coat is made of acrylic emulsion, water, 425# cement (a cement grade in China, which means an cement with a compressive strength of greater than 425 kg/cm² at 28 days under specified proportion and conditions), quartz sand, METHOCEL™ brand cellulose ether, and defoamer. The high strength skim coat includes Portland cement only, and silica and the surface textures of skim coat layer are formed by adopting special roller.

CN101205443A provides an adhesive powder used for decorated insulating panels for exterior walls, comprising cement, sand, calcium carbonate, polymer powder and other additives, wherein the polymer powder is ethylene vinyl acetate (EVA) re-dispersible powder. Said adhesive includes only Portland cement.

There are many problems in these conventional EIFS systems. For example, the basecoat mortar layer, which is used for the protection of insulation board and the substrate of coating, are made of normal polymer modified cement mortars formulated with cement, silica sand, polymer emulsion/powder, fillers and additives and applied by hand. The major issues for such basecoat mortar include slow strength gain, very poor performance such as adhesion and impact resistance at the early stage, high water absorption, heavy weight and no thermal insulation, which will give rise to long demolding time and plant export time, poor durability such as freeze-thaw resistance, difficulty in handling during installation due to heavy weight, difficulty in cutting at construction site with hard sand in the formulation and high deformation risk of insulation board.

A prefabricated panel has unique advantages over the systems requiring on- site construction. But when conventional polymer modified cement mortar is used as a base layer for the protection of insulation board in the production of the prefabricated panel, such a base layer of mortar also brings many issues, such as slow strength gain, very poor performance such as adhesion and impact resistance at the early stage, high water absorption, weight and absence of additional thermal insulation effect. In addition, such panel with polymer modified mortar is not suitable for assembly line production due to it being sticky with poor workability and slow strength development. When a high density cement fiber board is used as a base layer in the existing integrated panels in the market, the issues include long demolding time and plant export time, poor durability such as freeze-thaw resistance, difficulty in handling during installation due to heavy weight, difficulty in cutting at construction site and high deformation risk. In order to avoid wet expansion, high density fiberboard (> 1.4 g/cm³) is normally used as the facing layer of integrated panels and should be thick enough to achieve the required impact resistance to increase the total weight of integrated panel. In addition, such high density fiberboard is not easily bonded with sealants and may cause water leakage.

A formulated multifunctional facing layer which can overcome the existing issues of EIFS basecoat mortar is desirable. Such layer could combine with a thermal insulation board to achieve the required performance and overcome the above- mentioned issues. At the same time, an integrated panel is also desirable for exterior thermal insulation systems, which could be easily prefabricated in a quality-controlled environment. For public buildings, builders want an exterior thermal insulation system with easy application and maintenance, fewer failure opportunities, reliable fixing and fancy surface decoration. It is also desirable for different decoration patterns to be easily formed on its surface with the advantages of rich and artistic appearances, e.g. tile, stone and metal simulation, and at the same time light weight for easy handling and safety, fast installation, high weatherability and reliability at reasonable cost.

BRIEF SUMMARY OF THE PRESENT INVENTION

The present invention solves one or more of the problems associated with achieving the aforementioned desirable features for an EIFS article.

The present invention provides a multifunctional facing composition as the base coat layer (multifunctional facing layer) of EIFS articles to protect the insulation board of the EIFS articles. Specifically, the multifunctional facing composition is a multi-hydraulic binder composition, preferably a two-cement composition, that includes Portland cement, high alumina cement, hollow float beads, synthesized fibers, fillers, polymer emulsion/powder, and optionally other additives, such as accelerator, defoamer, thickener, superplasticizer, reinforcing material, etc. Compared with a traditional mortar composition, the multifunctional facing composition of the present invention has a two-cement composition that accelerates the strength gain and shortens curing time, and surprisingly is found to achieve excellent performance in many important parameters of EIFS system, such as the weight, impact strength, adhesive strength while applied on the thermal insulation board. The present invention also provides an integrated panel having shortened hardening time and better cutability, and therefore compared with other products in the art, such panel is suitable for mass production. The finished product is lightweight and achieves higher impact resistance having no use of glass fiber mesh. If desired, glass fiber mesh could also be embedded therein. The multifunctional facing layer also has a better adhesion with the thermal insulation board than traditional mortar compositions. At the same time, a decorative layer could be conveniently formed as a surface layer to simulate different patterns, such as stone-like, stucco, tile, etc. The present invention also provides a process to easily manufacture such a panel with a decorative layer.

In the first aspect, the present invention relates to an integrated panel comprising a thermal insulation layer having a surface, and a multifunctional facing layer applied on the surface of the thermal insulation layer, wherein the multifunctional facing layer is made of a multifunctional facing composition comprising a multi-hydraulic binder composition that comprises at least one accelerating binder and polymer emulsion or polymer powders.

The multi-hydraulic binder composition can comprise Portland cement and high alumina cement. The accelerating binder can be high alumina cement.

The multi-hydraulic binder composition can further comprise lightweight aggregates, reinforce material, such as synthesized fiber, and fine fillers.

The thermal insulation layer of the present invention may be selected from the group consisting of extruded polystyrene foam board, expanded polystyrene foam board, polyurethane foam board, phenolic foam board, mineral wool and foamed glass.

The lightweight aggregates can be selected from hollow float beads, expanded perlite, agglomerated ceramsite, vermiculite, and foamed glass beads.

The integrated panel of the present invention further can comprise a decorative layer, also named as decorative coating layer, wherein the decorative layer is formed on the multifunctional facing layer. The decorative coating layer can be fluorocarbon paints, latex paints, stone-like paints, or acrylic, styrene-acrylic, silicone-acrylic, or polyurethane based paints.

The integrated panel of the present invention further can comprise a primer composition layer applied between the multifunctional facing layer and the thermal insulation layer. Preferably, the primer composition layer is derived from acrylic emulsion. Preferably, the primer composition layer comprises a first layer of acrylic emulsion and a second layer consisting of silicate cement, high aluminum cement, polymer emulsion and other additives.

Preferably, the multifunctional facing layer further comprises synthesized fibers.

The multifunctional facing layer can further comprise accelerator, hydrophobic agent, superplasticizer, defoamer and thickener. Preferably, the multifunctional facing layer further comprises defoamer, superplasticizer, accelerators, hydrophobic agent, synthesized fibers and thickener.

Preferably, the thermal insulation board is grooved for additional mechanical interlocking between the multifunctional facing layer and the thermal insulation board. More preferably, the thermal insulation board is grooved on both sides for additional mechanical interlocking between the multifunctional facing layer and a wall substrate.

Preferably, the multifunctional facing layer is embedded with glass fiber mesh. The integrated panel can comprise a protective layer attached to the thermal insulation layer and located between the thermal insulation layer and a wall substrate on which the thermal insulation layer will be installed.

Preferably, the integrated panel further comprises an adhesive layer, which is optionally a layer made of polymer modified mortar, used to adhere the thermal insulation layer to the wall substrate, and in case of a protective layer included, the protective layer is located between the adhesive layer and the thermal insulation layer.

In the second aspect, the present invention relates to a process for producing the integrated panel of the present invention, the process comprising the steps of: (a) casting a multifunctional facing layer onto a filtration layer; (b) placing a thermal insulation layer onto the multifunctional facing layer; and (c) applying differential pressure to remove excessive water from the multifunctional facing layer and to form the integrated panel, wherein the multifunctional facing layer comprises a multi- hydraulic binder composition comprising at least one accelerating binder, lightweight aggregates, polymer emulsion and/or polymer powders, synthesized fibers, and fine fillers.

Preferably, the differential pressure results from a vacuum. More preferably, the process further comprises a step of applying a decorative layer onto the multifunctional facing layer during vacuum filtration.

Preferably, the differential pressure results from applying pressure on the multifunctional facing layer or the thermal insulation layer.

More preferably, the differential pressure is applied in two stages. In the first stage a pressure is applied before the thermal insulation layer is applied onto the multifunctional facing layer and in the second stage pressure is applied after the thermal insulation layer is applied onto the multifunctional facing layer.

Preferably, the process further comprises a step of forming designed patterns on the surface of multifunctional facing layer by putting a patterned mold plate on the top of the filtration layer.

The filtration layer can comprise a punching board, such as a punctured steel plate, filter cloth and filter paper.

Preferably, the process further comprises a step of applying a protective layer on the thermal insulation layer to achieve fire protection and improved adhesion, which is located between the thermal insulation layer and a wall substrate on which the thermal insulation layer will be installed.

More preferably, the process further comprises a step of applying an adhesive layer to adhere the thermal insulation layer to the wall substrate and the protective layer is located between the adhesive layer and the thermal insulation layer.

BRIEF DESCRIPTION OF DRAWING

Reference is made to the detailed description thereof to be read in connection with the annexed drawings wherein:

FIG. 1. Illustration of one example of an integrated panel.

FIG. 2. Illustration of another example of an integrated panel.

FIG. 3. Illustration of vacuum water removal molding process.

FIG. 4. Vacuum water removal production process in face-upward way.

FIG. 5 Illustration of one example squeezing process to remove excessive water from the multifunctional facing layer.

FIG. 6. Illustration of one example squeezing process to bind the thermal insulation layer and the multifunctional facing layer together.

FIG. 7. Illustration of one example of the mold and pressing plate. DETAILED DESCRIPTION OF THE PRESENT INVENTION

In the following detailed description, the specific embodiments of the present invention are described in connection with its preferred embodiments. However, to the extent that the following description is specific to a particular embodiment or a particular use of the present techniques, it is intended to be illustrative only and merely provides a concise description of the exemplary embodiments. Accordingly, the invention is not limited to the specific embodiments described below, but rather the invention includes all alternatives, modifications, and equivalents falling within the true scope of the appended claims.

As used herein:

Unless otherwise stated, all percentages (%) are by weight based on the total weight of the dry mortar composition. The descriptions of the various ingredients set forth below are non-limiting.

The "exterior insulation finish system (EIFS)" is an exterior wall cladding system, also known as External Thermal Composite Insulation Systems (ETICS) in Europe. It can be used on both residential and commercial buildings for purpose of energy saving, improving room comfort and protecting walls against moisture and other external elements.

The "mortar composition", depending on different components, may be classified into "cement mortar" and "polymer modified mortar". Cement mortar usually means a mortar composition comprising cement and fillers but having no emulsion polymer and other polymer-containing additives. Polymer modified mortar usually means a mortar composition comprising cement, fillers, emulsion polymer and other additives.

The "extruded polystyrene layer" or "extruded polystyrene (XPS) foam board" refers to a foam board prepared by expelling an expandable styrenic polymer foam composition comprising a polymer and a blowing agent from a die and allowing the composition to expand into a polymeric foam. Typically, extrusion occurs from an environment of a pressure sufficiently high so as to preclude foaming to an environment of sufficiently low pressure to allow for foaming. Generally, extruded foam is a continuous, seamless structure of interconnected cells resulting from a single foamable composition expanding into a single extruded foam structure. However, one example of extruded foam includes "strand foam". Strand foam comprises multiple extruded strands of foam defined by continuous polymer skins with the skins of adjoining foams adhered to one another. Polymer skins in strand foams extend only in the extrusion direction of the strand.

The thickness of the XPS foam board can vary depending on climate, humidity, etc. at construction site, and the energy saving requirements in different climate zones. Normally the XPS foam board has a thickness of about 20 to about 150 millimeters (mm), but can have a greater thickness

The "expanded polystyrene layer" or "expanded polystyrene (EPS) foam board" refers to a foamed board comprising multiple foamed styrenic polymer beads adhered to one another prepared in an expandable polymer bead process by incorporating a blowing agent into granules of polymer composition (for example, imbibing granules of polymer composition with a blowing agent under pressure). Subsequently, expand the granules in a mold to obtain a foam composition comprising a multitude of expanded foam beads (granules) that adhere to one another to form "bead foam." Pre-expansion of independent beads is also possible followed by a secondary expansion within a mold. As yet another alternative, expand the beads apart from a mold and then fuse them together thermally or with an adhesive within a mold.

The "thermal insulation board" means thermal insulation materials in the form of board, which can be the thermal insulation layer of EIFS. The core of EIFS application is to attach thermal insulation materials to the substrate wall by using adhesive materials. The outer surface of EIFS is further completed by other finish materials such as stucco, painting or ceramic tile. Preferably, the thermal insulation materials can be selected from the group consisting of EPS foam board, XPS foam board, polyurethane foam board, phenolic foam board, mineral wool and foamed glass, all of which can provide thermal insulation to the building under insulation/energy codes. A multi-functional facing layer is typically adjacent to the thermal insulation board and optionally, a primer composition layer may be applied between them.

"Finish layer", also named as "decorative layer" or "decorative coating layer", is normally the outmost surface of the composite structure, i.e. the integrated panel, for aesthetic purpose, which could be a painting layer, a ceramic tile, or a stucco layer. "Multifunctional facing layer" is located between the thermal insulation board and decorative coating layer (if any) in EIFS, which is attached to the thermal insulation board and used as a protective, mechanical abuse layer, as well as a substrate for adhesives, insulation, impact resistance, fire resistance. In the present invention the multifunctional facing layer is made of a multifunctional facing composition comprising a multi-hydraulic binder composition that comprises at least one accelerating binder and polymer emulsion or polymer powders. The composition can further comprise lightweight aggregates, polymer emulsion or polymer powders, synthesized fiber, fine fillers and other additives. Normally the composition comprises two kinds of binders at the same time, inorganic binder, such as cement, and organic binder, such as acrylic emulsion or polymer powder.

"Polymer powder" is also named as "re-dispersible power (RDP)", which is made by spray drying emulsion polymer in the presence of various additives such as a protective colloid, anti-caking agent, etc. Many types of polymers can be used to produce RDP including ethylene/vinylacetate copolymer (vinyl ester-ethylene copolymer), vinylacetate/vinyl-versatate copolymer, styrene/acrylic copolymer, etc. To carry out spray drying, the dispersion of the copolymer, if appropriate together with protective colloids, is sprayed and dried. When mixed with water, these polymer powders can be re-dispersed to form an emulsion, which in turn forms continuous films within cement mortar later when the water is removed by evaporation and hydration of cement.

Preferred vinyl esters comprise vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate, 1 -methylvinyl acetate, vinyl pivalate, and vinyl esters of alpha-branched monocarboxylic acids having from 5 to 1 1 carbon atoms. Some preferred examples include VEOVA™ 5 RTM., VEOVA™ 9 RTM, VEOVA™ 10 RTM., VEOVA™ 11 RTM (VEOVA is a trademark of Resolution Performance Products, L.L.C.) or DLP 2140 redispersible polymer powder (available from The Dow Chemical Company). Preferred methacrylic esters or acrylic esters include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, and 2- ethylhexyl acrylate. Preferred vinyl- aromatic s include styrene, methyl styrene, and vinyltoluene. A preferred vinyl halide is vinyl chloride. The preferred olefins are ethylene and propylene, and the preferred dienes are 1,3-butadiene and isoprene. The polymer powder fraction can be, though is not necessarily limited to being, from about 0.1 to about 20% by weight of the total weight of the multifunctional facing layer. In another example it is from about 1 to about 10% by weight, and in another example from about 2 to about 5% by weight of the total weight of the multifunctional facing layer.

The "polymer emulsion" or "polymer dispersion" means a two phase system having finely dispersed polymeric particles in solvent such as water. The polymer emulsion or polymer dispersion is typically an aqueous dispersion of polymer particles, which normally comprises polymeric particles, such as vinyl polymer or polyacrylic ester copolymer and a surfactant containing hydrophobic and hydrophilic moieties. Polymer emulsion when applied as a coating on a substrate and cured at ambient or elevated temperature, has been found to have excellent solvent, chemical and water resistance, exterior durability, impact resistance, abrasion resistance, e x c e l l e n t a d h e s i o n t o a v a r i e t y o f s u b s t r a t e s e t c .

A "primer composition" is normally used to form a primer composition layer that adheres surfaces together. The primer composition used in EIFS is also a member of emulsion polymer and normally water-dispersible. One example of a primer composition comprises (poly)acrylic emulsion. The primer composition can be brushed onto the surfaces of various kinds of substrates, such as the thermal insulation board. Sometimes, a primer composition (such as some commercialized products) may be further diluted at the construction site by corresponding solvent, normally water.

The primer composition layer in the present invention can comprise a layer of emulsion polymer. Preferably, in addition to the layer of emulsion polymer, the primer composition layer in the present invention may further comprise a second layer that is composed of emulsion polymer, silicate cement, high alumina cement, and other additives, such as thickeners.

The primer composition is applied preferably in an amount of about 20 grams per square meter (hereinafter "g/m²") to about 150g/m², more preferably from about 50g/m² to about 100g/m², and even more preferably from about 60g/m² to about 80g/m² of the surface of the thermal insulation board.

The "viscosity modification agent" or "thickener" is used in construction industry to modify the viscosity of the mortar composition. Examples of thickeners are any one or combination of more than one of: polysaccharides such as cellulose ethers and modified cellulose ethers, starch ethers, guar gum, xanthan gum, phyllosilicates, polycarboxylic acids such as polyacrylic acid and the partial esters thereof, optionally acetalized and/or hydrophobically modified polyvinyl alcohols, casein, and associative thickeners. .Preference is given to cellulose ethers, modified cellulose ethers, optionally acetalized and/or hydrophobically modified polyvinyl alcohols, and mixtures thereof.

The thickener fraction is typically from 0.01% to 1% by weight based on the total weight of the multi-functional facing layer and can be from 0.03% to 0.7% by weight based on the total weight of the multi-functional facing layer, or even from 0.05% to 0.4% by weight based on the total weight of the multi-functional facing layer.

In construction systems such as mortar composition, renderings, stuccos, flooring systems and building adhesives, flow control is very important. The main additive used to provide thickening and water retention is cellulose ether. However, it is found that the system performance and application behavior can be significantly improved by using one or more rheological agents in combination with cellulose ethers.

The "hydraulic binder", which is widely used in construction industry, means a mineral composition of finely ground materials which upon addition of an appropriate quantity of water forms a binding paste or slurry capable of hardening in air as well as under water and binding together the granulates. The hydraulic binder usually comprises one or more materials selected from clinkers, cements, slags, fly ashes and pozzolanic materials. Typically, the materials of the hydraulic binder have a particle size of 200 microns (hereinafter "μπι") or less.

The hydraulic binder fraction is typically from 10% to 80% by weight based on the total weight of the multifunctional facing layer and can be from 20% to 50% by weight based on the total weight of the multifunctional facing layer, or even from 25% to 45% by weight based on the total weight of the multifunctional facing layer.

One example of hydraulic binder is cement. Cement provides adhesive strength to substrate through hydration process in the presence of water. The sufficient hydrated cement has high mechanical strength as well as water resistance, but the flexibility is relatively low. Due to functional requirements in applications such as EIFS, the cement has to be modified by flexible polymers.

In the present invention, a "multi-hydraulic binder composition" means a hydraulic binder composition comprising more than one hydraulic binder, preferably comprising at least one accelerating binder. Any appropriate hydraulic binders used in conventional mortar composition could be used in the present invention. Preferably, such multi-hydraulic binder composition is a two-cement composition. More preferably, the multi-hydraulic binder composition consists of Poland cement, and high alumina cement as the accelerating binder.

"High alumina cement (HAC)" means a cement in which monocalcium aluminate (CA) as the principal cementing compounds with C12A7, C2AS, PC2S, and Fss as minor compounds. Typically, the chemical analysis of ordinary HAC corresponds to approximately 40 percent AI2O₃, and some cements contain even higher alumina content (50 to 80 percent).

"Accelerating binder" means a hydraulic binder which could be quick-setting ("quick setting" means setting in 2-20 minutes and preferably 3-10 minutes as opposed to an hour or more). In a specific embodiment, such accelerating binder is a hydraulic binder containing reactive calcium aluminates, in particular high alumina cement.

"Accelerator" usually means a chemical substance mixed with cement slurry to reduce the time required for setting and hardening cement to develop sufficient compressive strength to enable demolding or drilling operations to continue. The most conventional are, e.g., nitrate, formate, thiocyanate, nitrite, mono-, di- and triethanolamine, highly alkaline agents like alkali hydroxide, alkali carbonate, alkali silicate, alkali aluminate as well as alkaline earth metal chlorides. US5,605,571 also teaches an accelerator for hydraulic binders containing at least a nitrate- or sulfite component, at least a thio-cyanate component, at least an alkanolamine component and at least a carboxylic acid component.

"Fine filler" is an aggregate that is widely used in conventional EIFS and refers to inorganic material without binding function. Fine filler is used to 1) reduce cement content for less dry shrinkage and cost; 2) improve workability; 3) improve mechanical performances due to its densification; and 4) obtain enough paste content in mixture for wrapping light weight aggregates. The particle size of fine filler is small, generally less than 0.1mm. One example of fine filler is limestone (calcium carbonate) powder (250 mesh, equivalent to a size of 0.058 mm).

Fine filler is typically present at a concentration of from 0 to 20% by weight based on the total weight of the multifunctional facing layer, or from 5 to 15% by weight based on the total weight of the multifunctional facing layer, or even 8 to 12% by weight based on the total weight of the multifunctional facing layer.

"Lightweight aggregates" are minerals, natural rock materials, rock-like products, and byproducts of manufacturing processes that are used as bulk fillers in lightweight structural concrete, concrete building blocks, precast structural units, road surfacing materials, plaster aggregates, and insulating fill. Lightweight aggregates are also used in architectural wall covers, suspended ceilings, soil conditioners, and other agricultural uses.

Lightweight aggregates may be classified into four groups:

(1) Natural lightweight aggregate materials which are prepared by crushing and sizing natural rock materials, such as pumice, scoria, tuff, breccia, and volcanic cinders.

(2) Manufactured structural lightweight aggregates which are prepared by pyroprocessing shale, clay, or slate in rotary kilns or on traveling grate sintering machines.

(3) Manufactured insulating ultralightweight aggregates which are prepared by pyroprocessing ground vermiculite, perlite, and diatomite.

(4) Byproduct lightweight aggregates which are prepared by crushing and sizing foamed and granulated slag, cinders, and coke breeze.

Lightweight aggregates are distinguished from other mineral aggregate materials by their lighter unit weights. They typically have a weight less than 1 120 kg/m³. Use of lightweight aggregate allows builders to install a concrete with a much less weight than those made with heavy aggregates. In addition to its weight savings, manufactured lightweight aggregate is valued because of its skid resistance, thermal insulating abilities, and strength.

Light weight aggregate can be present in the present invention at a concentration of from 10 to 80% by weight based on the total weight of the multifunctional facing layer, or from 20 to 60% by weight based on the total weight of the multi-functional facing layer, or even 30 to 45% by weight based on the total weight of the multi-functional facing layer.

"Reinforcing materials" is widely used in construction industry and means organic or inorganic materials mixed into mortar to obtain some desirable performances, such as increasing impact resistance, anti-crackle, etc. Synthesized fibers and glass fiber mesh are two kinds of reinforcing materials which are most often used. In addition, suitable natural fibers and inorganic fibers could also be used in the present invention.

"Synthesized fibers", also named as "polymer fibers", are used to reinforce or otherwise improve the properties of concrete by applying them to aqueous based concrete mixes prior to the curing of the concrete. The types of synthesized fibers in use or proposed for use include those composed of polyolefins, especially polypropylene, polyester, polyamide, polyacrylic and polyvinyl alcohol.

Polypropylene fibers can be produced by a well known melt spinning process. The use of polypropylene fibers is desirable for several reasons, including low raw material cost, excellent physical properties, and the nonreactive properties of the polymer in the alkaline concrete mix.

The "glass fiber mesh" is normally made of white and odorless fabric. An example is white C-glass fiber woven fabric, coated with SBR (styrene butadiene rubber latex), with various mesh size (4x4 millimeter (hereinafter "mm"), 5x5mm, 4x5mm etc.) and surface weight(135, 145, 160, 200, 300g/m² etc.). Used as additional reinforcement fabric embedded in the middle of EIFS basecoat mortar for surface to resist cracking and impact. A roll is sufficient for approximately 45 m² (lm wide, 50m long, but 1.1m² per m² of surface).

The "differential pressure" is the pressure difference between two sides of a layer, such as a multifunctional facing layer. When two or more layers are combined together into one composite layer, the differential pressure is the pressure difference between the top side and bottom side of the composite layer. The differential pressure could be generated from vacuum, normally negative pressure in a closed chamber, or pressure, i.e normally positive pressure.

The pressure could be applied in many ways, such as mechanically. The pressure may be produced from a hydraulic pressure system. The differential pressure can be applied in two stages. In the first stage, only the multifunctional facing layer is placed under the differential pressure to remove excessive water therein. In the second stage, the differential pressure is applied to combine the multifunctional facing layer and the thermal insulation layer together.

In the first stage, the pressure range is typically from 0.1 - 0.6 million Pascal

(hereinafter "MPa") and the pressure lasts around 8-24 seconds. Preferably, the pressure range is from 0.4 - 0.5 MPa and the pressure lasts around 18-22 seconds.

In the second stage, the pressure range is typically from 0.05 - 0.2 MPa and the pressure lasts around 5-15 seconds. Preferably, the pressure range is from 0.13 - 0.15 MPa and the pressure lasts around 8-12 seconds.

The differential pressure could also be obtained through vacuum, such as negative pressure at one surface of the multifunctional facing layer or the thermal insulation layer. The vacuum is 0.01-0.06Ma and lasts 3-30 minutes. The vacuum typically is 0.02-0.04Ma and lasts 5-20 minutes.

The integrated panel of the present invention can be illustrated as follows. An integrated panel comprises a thermal insulation board 1, a multifunctional facing layer 2 applied onto the thermal insulation board 1. See Fig. l . A decoration and thermal insulation integrated panel comprises a thermal insulation board 1, a multifunctional facing layer 2 applied onto the thermal insulation board 1 and a decorative coating layer 3 applied on the top of the multifunctional facing layer 2. See Fig.2. Preferably, the integrated panel could further comprise a primer composition layer 4, which is located between the thermal insulation board 1 and the multifunctional facing layer 2.

The multifunctional facing layer 2 comprises Portland cement, high alumina cement, polymer emulsion/powder, polypropylene fiber, accelerator, hollow float beads, filler and other additives, such as defoamer, thickener, superplasticizer, etc.

The thermal insulation board 1 is a pre-formed board made of XPS, EPS, PU, phenolic foam, mineral wool or foamed glass.

The decorative coating layer 3 in an integrated panel can be aqueous paints. Preferably, it can be fluorocarbon paints, acrylic based latex paints, styrene-acrylic based latex paints, silicone-acrylic based latex paints, polyurethane paints, stone-like paints.

The integrated panel can comprise a protective layer (not shown in FIGs.1 and 2) which is located between a wall substrate and the thermal insulation board and provides adhesion to the wall substrate and additional fire protection. The protective layer is made of a composition comprising cement, such as Portland cement and high alumina cement, polymer emulsion/powder, synthesized fiber, accelerator, hollow float beads, filler and other additives, such as defoamer, thickener, superplasticizer, etc.

A production process of the integrated panel is illustrated in FIG. 3 and described as follows. A fresh mixture of a multifunctional facing composition is poured onto a filtration layer (combination of al, a2 and a3) which is located on a filterable plate 6 in a mold 5. A multifunctional facing layer 2 is formed on the filtration layer. A thermal insulation board 1 is placed on the multifunctional facing layer 2 with a specially formulated primer composition layer 4 pre-applied on its surface strengthening adhesion to the multifunctional facing layer 2. Gap 8 is left between the lateral sides of the thermal insulation board 1 and the internal wall of the mold 5. Vacuum is applied to remove excessive water passing through the filtration layer and filterable plate 6. Vacuum could be applied over an extended time to keep the above-mentioned layers to tightly contact with each other. The mold 5 is moved out and turned over upside down to demold the integrated panel by carefully removing the filtration layer. The integrated panel is then cured and treated, e.g. polishing if necessary. Finally, if necessary, decorative coatings (not shown in FIG.

3) are applied; protective film (not shown in FIG. 3) is cured and adhered to finish the whole manufacture process of the integrated panel.

Preferably, the surface of fresh mixture of the multifunctional facing layer 2 is leveled with vibration and/or toweling before the thermal insulation board 1 is placed thereon.

Preferably, vacuum could be applied in two stages: in the first stage, pre- vacuum is applied immediately after the multi-hydraulic composition is formed into a flat surface and before the thermal insulation board 1 is applied. After the thermal insulation board is applied, vacuum is re-applied as the second stage to make layers to attach with each other tightly.

Preferably, the filtration layer comprises, and optionally consists of filter paper a2, filter cloth a3, and optionally a punching board al. In demolding, the filter cloth a3 is carefully removed; the filter paper a2 is torn out; the punching board al (if used) is taken off.

A designed punching board al can be used which is a plate with through punched holes and therefore removed water could pass through it. Different textures can be designed on the punching board al, and therefore 3-D patterns can be formed on the surface of the multifunctional facing layer during the vacuum water removal process.

The punching board can be a plate made of metal, such as steel, copper or aluminum, or polymer material, such as PVC. The holes can be formed in any appropriate way and are scattered symmetrically on the surface of the punching board.

When a three-dimensional (3-D) pattern is needed on the surface of the multifunctional facing layer, a pattern forming plate a'(not shown in Fig.3) could be inserted between the multifunctional facing layer 2 and filter paper a2, and in this case different textures on the punching board al is not needed. The pattern forming plate, which could be made of any appropriate material, such as steel, copper, aluminum and PVC, has different textures on the surface contacting the multifunctional facing layer and has also scattered punctured holes.

The fresh mixture of the multifunctional facing layer 2 can be directly poured onto the filter paper a2 when the punching board al is not necessary. The filter paper a2 can be made from blended polyester and polyethylene. Besides used as a filtration media, the filter paper a2 is also used since it is easy to be torn out from cement paste.

The primer composition layer 4 can be composed of two layers: a first primer composition layer made of only acrylic emulsion and a second layer made of a mixture of silicate cement, high aluminum cement, polymer emulsion and necessary additives.

The thermal insulation board 1 can be punctured to make porous. Applying vacuum removes water passing through porous thermal insulation board 1 in following steps.

The thermal insulation board 1 can be grooved on one side for additional mechanical interlocking between the multifunctional facing layer 2 and the thermal insulation board 1. Optionally the thermal insulation board 1 is grooved on both sides.

As shown in Fig. 4, the thermal insulation board 1 could be placed on the filterable plate 6 first and then the fresh mixture of the multifunctional facing composition of the multifunctional facing layer 2 is poured onto the thermal insulation board 1. A pattern forming plate a' could be placed on the multifunctional facing layer 2. Then excessive water is removed from the multifunctional facing layer 2 through vacuum process. The integrated panel is demolded, then cured and treated, e.g. polishing if necessary. Finally, a decorative coating (if necessary) is applied and the protective film is cured and adhered to finish the whole manufacture process of the integrated panel product.

A process for manufacturing an integrated panel can comprise, and optionally consists of the following steps:

• casting a multi-hydraulic composition onto a filtration layer loaded in a mold;

• vibrating the fresh composition to obtain a flat surface thereof;

• applying pre-vacuum filtration process to remove excessive water of the multifunctional facing layer;

• spraying or brushing acrylic emulsion as a first primer composition layer and then acrylic emulsion formulated with cement as a second primer composition layer on one surface of a thermal insulation board;

• placing the thermal insulation board onto the pre-vacuumed multifunctional facing layer with the primer composition layers contacting with the multifunctional facing layer;

• applying pre-vacuum again to hold the layers tightly; and

• demolding when adhesion achieves the required strength to form the integrated panel.

The integrated panel can be fixed to an exterior wall substrate by many methods, such as adhesive mortar or mechanical fixing. For example, an adhesive layer could be used to adhere the integrated panel to a wall substrate.

As shown in Fig. 5, a glass fiber mesh can be placed on filterable plate 6 first and then the fresh mixture of multifunctional facing layer 2 is poured onto the glass fiber mesh. Pressing plate 9 can be placed on the multifunctional facing layer and then a pressure is applied on plate 9 to remove excessive water from said multifunctional facing layer. Such pressure application could also be called a squeezing process.

As shown in Fig. 6, after thermal insulation board 1 is placed onto multifunctional facing layer 2 (a primer composition layer located therebetween), a pressure and vibration can be applied on thermal insulation board 1.

The present invention can also comprise a protective layer. A protective layer can offer better fire protection and improved adhesion when fixing with a wall substrate. The protective layer can be applied onto the backside of the thermal insulation board before the multifunctional facing layer is applied on the thermal insulation board. "Backside of the thermal insulation board" means relative to the opposite surface, a surface of the thermal insulation board adjacent to the wall substrate onto which the thermal insulation board will be installed.

Glass fiber mesh can be embedded in the multifunctional facing layer to further improve impact resistance.

The size of the integrated panel can vary and can be based on specific requirements of construction. For example, the integrated panel can have dimensions of 1200mmx600mm and a sheet density of 30 kilogram per square meter (hereinafter "kg/m²") or less.

The thickness of the multifunctional facing layer may also vary based on specific requirements of construction. One desirable thickness is 5mm.

Desirably, the present invention has the following performance characteristics: adhesive strength of the multifunctional facing layer to the thermal insulation board of 0.2 MPa or more at 7 days; impact resistance of the multifunctional facing layer of 3 J or more at 7 days; water absorption of the integrated panel of 300g/m² or less.

EXAMPLES

Example 1

A vacuum water removal device is designed and assembled for casting the multifunctional facing layer with a thermal insulation board in the test. The device comprises a casting box (the mold) located on and connected to a vacuum room. A vacuum pump and a vacuum meter are connected with the vacuum room through pipes. Waster water exit is connected with the vacuum room.

A piece of grooved STYROFOAM™ Wallmate LB brand extruded polystyrene foam board (STYROFOAM is a trademark of The Dow Chemical Company) with a size of about 380mm(length)x260mm(width)x40mm(thickness) is used for the trial. Before casting the multifunctional facing layer compound, a primer composition layer including two layers with the formulations in Table 1 is applied on the surface of the foam board. The composition of the multifunctional facing layer is shown in Table 3. The composition is mixed with water and poured onto a filtration layer. The filtration layer is installed in the device, which includes a punching board, filtration cloth (available from Shanghai Yanpai Filter Cloth Co., Ltd.), and filter paper (available from Shanghai Mingguan Filter Paper Co., Ltd.). The punching board is a steel plate bearing though punched holes that are scattered symmetrically on the surface of the punching board. The fresh mixture of the composition was leveled by trowel and the primed STYROFOAM™ Wallmate LB board is pressed on its top with gaps left between the lateral sides of the foam board and internal wall of the device. Excessive water was removed from the multifunctional facing layer by applying low vacuum at the beginning to avoid segregation and then increasing vacuum to strengthen the adhesion of the layers. After that, the cast panel is moved out from the device and turned over upside down. The filter paper is easily removed just after the vacuum casting process. In less than one day, the integrated panel is hard enough to be sawed. There are no broken edges in the panel.

Simulated ceramic tile patterns can be formed on the surface of the multifunctional facing layer by using a pattern forming plate through the vacuum filtration process. After coating with fluorocarbon paint or stone-like paint, the panel is ready to be used for buildings with both functions of thermal insulation and decoration. The properties of impact resistance, dry and wet adhesion and sheet density are listed in Table 4, which can fulfill the requirements of the drafted code (JGJ 149-2003) and Beijing local code for decoration and thermal insulation integrated panels. At the same time, compared with products in the art (such as high density concrete fiber board), it shows comprehensive advantages over the similar products in the art, such as faster setting, lower density, higher adhesive strength and impact resistance, and at the same time it is easy to cut.

In an example, the integrated panel further comprises a protective layer as shown in Table 5, which is brushed on the backside of the thermal insulation board.

Table 1 : Formulation of a primer composition layer: Component Part by weight

First primer Tianba™ 2000 50.00 composition layer Triton™ CF-10 0.12

Foabique™ H- 100 0.10

Water 49.78

Total 100

Second primer Portland cement 91.50 composition layer High alumina cement 8.00

MKX 6,000 PF01 (Dow Chemical) 0.20

Elotex™ Seal 80 (Akzo Nobal) 0.30

Total 100

Tianba and Triton are trademarks of Dow Chemical.

Foabique is a trademark of Shanghai Shicheng Chemicals Co. Ltd.

Elotex is trademark of Akzo Nobal.

Table 2

Alternative example of a primer composition layer

FONDU is a trademark of Kerneos Societe Anonyme France Table 3. Composition of a multifunctional facing layer

Lithium Carbonate 0.10

WALOCEL™ MKX 6,000 PF01 (Dow) 0.10

Defoamer (EFKA™ 2550) 0.15

Acrylic emulsion (R&H 968 LO) 5.00

ELOTEX™ Seal 80 0.30

ELOTEX™2350 2.00

Super plasticizer (KERNEOUSTM SM10) 0.30

Total 100

Mixing water 35% of the total formulation

KERNEOS and FONDU are trademarks of Kerneos Societe Anonyme France

EFKA is a trademark of CIBA Corporation

ELOTEX is a trademark of Akzo Nobel SPG LLC Corporation

WALOCEL is a trademark of Dow Chemical

Table 4

Note: Testing is conducted based on the draft version of the industrial code for insulative decoration panel drafted by China Building Materials Academy and the existing EIFS code of JGJ149-2003. The test result show better performances than those in the industrial codes. The time to cast facing layer with vacuum water removal process needs 5-10 min depending on the leakproofness of vacuum equipment.

Table 5: In an example, the protective layer has a composition as follows.

Example 2

A mold for squeezing process shown in Fig.7 is designed and assembled in Shanghai Huayu Machinery Co. Ltd. for casting the multifunctional facing layer. A piece of grooved STYROFOAM™ Wallmate LB board with the size of 900 600 mm was used for the trial. Before casting the multifunctional facing composition, a first primer composition layer and then a second primer composition layer are applied onto the foam board. Their formulations are shown in Table 6. The multifunctional facing composition with the formulation shown in Table 7 was mixed with water and placed onto a filtration layer. The filtration layer shown in Fig.5 includes a punching steel plate machined by Huayu, filtration cloth bought from Shanghai Yanpai Filter Cloth Co., Ltd., and filter paper bought from Shanghai Mingguan Filterpaper Co., Ltd. The size of the punching steel plate, filtration cloth and filter paper could be adjusted to make fit for the mold. The punching steel plate is adjacent to the multifunctional facing layer and the filter paper is placed between the steel plate and the filter cloth. Then, a piece of glass fiber mesh with the size of 900x600 mm is put onto the filtration layer. The fresh mixture of the multifunctional facing composition in the mold is leveled by a trowel and a piece of filtration paper is laid to separate the fresh mixture and the pressing plate. Then the whole mold is pushed to the position for squeezing. A hydraulic pressure system is used to squeeze the fresh facing compound under the pressure of 20 Ton for around 15 seconds. Small amount of water was removed from the multifunctional facing layer by the squeezing process. After that, the mold is dragged out and thus a fresh multifunctional facing layer having flat surfaces and uniform thickness is obtained. The foam board (primed) is put on the top of the multifunctional facing layer for bonding under pressure. The cast panel is moved out from the mold and turned over. The filter paper is easily torn out under the help of the glass fiber mesh. The glass fiber mesh can also improve significantly impact resistance. After less than one day, the integrated panel is already hard enough to be sawed and ready to be coated with fluorocarbon paint or stone-like paint with both functions of thermal insulation and decoration. The properties of impact resistance, dry adhesion and sheet density are listed in Table 8, which can fulfill the requirements of the national drafted code for decoration and thermal insulation integrated panels. Table 6: The formulations of a first primer composition layer and a second primer composition layer

Table 7: The formulation of the multifunctional facing composition

Table 8 : Properties of the integrated panel

Note: *The properties are tested based on the draft version of JGJ144-2009 Example 3

A multifunctional facing composition is formulated according to the formulation shown in Table 9. The vacuum water removal process is used to cast the multifunctional facing layer. Glass fiber mesh is not combined with it. The multifunctional facing layer can achieve a fast gain and be demoulded after 3-5 hours. The physical properties of the facing layer are shown in Table 10. The specs are based on the codes of JG 149-2003 and JGJ144-2005

Table 9 Formulation of the multifunctional facing composition for vacuum water removal process

Table 10: The physical properties of the facing layer formulated with Table 1

Facing layer Unit Measured

Adhesive strength Dry* 0.52

MPa

with Styrofoam Wet** 0.24

Water absorption g/m2 397

Impact resistance Without glass fiber mesh J >3.0 Weatherability test*** (80 cycles of dry hot /

conform wet cold and 5 cycles of freeze / thaw

* Specimens were cured at 23±2°C and 50±5% r.h. for 3 days

** Specimens were cured at 23±2°C and 50±5% r.h. for 3 days and then immerged in water for 7 days

*** Specimens were cured at 23±2°C and 50±5% r.h. for 7 days

Example 4

A multifunctional facing composition based on the formulation shown in Table 1 1 is also formulated. The squeezing process with pressure applied on the top of the fresh composition by a steel plate is used to cast the multifunctional facing layer. Glass fiber mesh is placed in the mold for a squeezing process and embedded into the multifunctional facing layer through the process. The physical properties of the multifunctional facing layer are shown in Table 12. The specs are based on the codes of JG 149-2003 and JGJ144-2005.

Table 11 : The formulation of the facing compound for squeezing process

Table 12: The physical properties of the multifunctional facing layer Integrated panel Unit Measured

Adhesive strength Dry* 0.51

MPa

with Styrofoam Wet** 0.37

Water absorption* g/m2 398

Impact With glass

J 4

resistance* fiber mesh

* Specimens were cured at 23±2°C and 50±5% r.h. for 3 days

** Specimens were cured at 23±2°C and 50±5% r.h. for 3 days and then immerged in water for 7 days The properties of the multifunctional facing layer according to the present invention can achieve the requirements in the relevant Chinese codes. Compared with the existing facing layers, the multifunctional facing layer of the present invention can bring the following benefits: a) light weight with bulk density less than 1.0 g/cm3 ; b) fast strength development: demoulded after 6-8 hours curing and achieve the code requirements after 3 day curing at normal temperatures; c) easy to cut with handsaw at site; d) impact resistance to meet the code requirements; e) weatherability to stand dry hot / wet cold and freeze / thaw cycles without deformation and wet expansion; f) thermal and sound insulation; g) low shrinkage without giving rise to deformation after hot / cold cycles; h) fire protection with A grade achievable.

Claims

1. An integrated panel comprising:

(a) a thermal insulation layer having a surface, and

(b) a multifunctional facing layer applied on the surface of said thermal insulation layer,

wherein said multifunctional facing layer comprises a multifunctional facing composition comprising a multi-hydraulic binder composition that comprises at least one accelerating binder and polymer emulsion or polymer powders.

2. The integrated panel according to claim 1, wherein said accelerating binder is high alumina cement.

3. The integrated panel according to claim 1, wherein said multi-hydraulic binder composition comprises Portland cement and high alumina cement.

4. The integrated panel according to claim 1, wherein said thermal insulation layer is selected from the group consisting of extruded polystyrene foam board, expanded polystyrene foam board, polyurethane foam board, phenolic foam board, mineral wool and foamed glass.

5. The integrated panel according to claim 1, wherein said multi-hydraulic binder composition comprises lightweight aggregates, polymer emulsion or polymer powders, reinforce materials, fine fillers and at least one accelerating binder.

6. The integrated panel according to claim 1, wherein said lightweight aggregates are selected from the group consisting of hollow float beads, expanded perlite, agglomerated ceramsite, vermiculite, and foamed glass beads.

7. The integrated panel according to claim 1, wherein said multifunctional facing layer is embedded with glass fiber mesh.

8. The integrated panel according to claim 1, further comprising a decorative coating layer, wherein said decorative coating layer is affixed to said multifunctional facing layer.

9. The integrated panel according to claim 1, further comprising a primer composition layer residing between said multifunctional facing layer and said thermal insulation layer.

10. The integrated panel according to claim 9, wherein said primer composition layer is made of acrylic emulsion.

1 1. The integrated panel according to claim 9, wherein said primer composition layer comprises a first layer made of acrylic emulsion and a second layer made of silicate cement, high alumina cement and polymer emulsion.

12. The integrated panel according to claim 1, further comprising a protective layer attached to the thermal insulation layer and located between the thermal insulation layer and a wall substrate on which said integrated panel will be installed.

13. A process for producing an integrated panel, the process comprising the steps of:

(a) casting multifunctional facing composition onto a filtration layer to form a multifunctional facing layer;

(b) placing a thermal insulation layer onto said multifunctional facing layer; and

(c) applying differential pressure to remove water from said multifunctional facing layer and to form said integrated panel,

wherein said multifunctional facing layer comprises a multifunctional facing composition comprising a multi-hydraulic binder composition which comprises at least one accelerating binder and polymer emulsion or polymer powders.

14. The process according to claim 13, wherein said thermal insulation layer is placed onto said filtration layer first and then said multifunctional facing composition is casted onto said thermal insulation layer.

15. The process according to claim 13, wherein said differential pressure is produced between said thermal insulation layer and said multifunctional facing layer and results from applying a vacuum.

16. The process according to claim 15, further comprising a step of applying a decorative layer onto said multifunctional facing layer during vacuum filtration.

17. The process according to claim 15, wherein the vacuum is applied in two stages, and in first stage vacuum is applied before the thermal insulation layer is applied onto the multifunctional facing layer and in a second stage is applied after the thermal insulation layer is applied onto the multifunctional facing layer.

18. The process according to claim 13, wherein the differential pressure results from applying pressure on said multifunctional facing layer.

19. The process according to claim 18, wherein said pressure is applied in two stages, and in the first stage a pressure is applied before said thermal insulation layer is applied onto said multifunctional facing layer and in a second stage is applied after said thermal insulation layer is applied onto said multifunctional facing layer.

20. The process according to claim 13, wherein said filtration layer comprises a punching board, filter cloth and filter paper.