WO2021001689A1

WO2021001689A1 - Thermally insulating coating composition

Info

Publication number: WO2021001689A1
Application number: PCT/IB2020/000572
Authority: WO
Inventors: Elio DI MARIA
Original assignee: GIUSEPPE DI MARIA S.p.A.
Priority date: 2019-07-01
Filing date: 2020-07-01
Publication date: 2021-01-07

Abstract

Compositions of the invention provide a thermally insulating coating and include a water dispersible polymer; an extender comprising calcium carbonate, and hollow glass spheres. Compositions of the invention can also include titanium dioxide, kaolin, cellulosic thickeners, dispersants (surfactants), Biocides, and other additives. Coatings prepared from compositions of the invention can also provide anti-condensation and anti-mold properties. The inventive compositions can be easily applied by a consumer or homeowner by brushing, rolling or spraying.

Description

THERMALLY INSULATING COATING COMPOSITION

BACKGROUND OF THE INVENTION

Field of the Invention

[0001] The present invention relates generally to a coating composition that provides thermally insulating, anti-condensation and anti-mold properties. More particularly the invention is a thermally insulation paint composition that includes a water dispersible polymer; calcium carbonate, hollow glass spheres, titanium dioxide, kaolin, cellulosic thickeners, dispersants (surfactants), Biocides, and other additives.

General Background

[0002] Heat transfer through walls can create a number of problems on the interior of a dwelling such as a home or rented rooms, for example in hotels. In some cases, these problems are associated with water condensation on walls from heat transfer through the walls resulting in surface temperatures different from air temperatures. Condensation on walls and building materials, that may include organic nutrients such as drywall and wood, creates the possibility for mold growth. Mold propagation is exacerbated by fluctuating temperatures caused by adjusting for internal temperatures rather than controlling humidity. Lack of control of humidity increases the likelihood of condensation and increases the risk of mold.

[0003] Once present, mold can affected other parts of a dwelling, for example,

wallpaper can trap and concentrate condensation and glue for wallpaper can provide nutrients for mold to thrive. Carpet and the padding underneath are also highly susceptible to mold.

[0004] Paints are on the market that claim to be anti-condensation formulations’

however, these paints are not very effective in simultaneously providing long term prevention of condensation and mold.

[0005] Additionally, heat transfer through walls can result in excessive heat buildup or loss of heat in the interior of a dwelling. Because of this influx or loss of heat, additional energy is required to cool or heat the dwelling, which can add significantly to energy costs.

[0006] While heat transfer can be reduced by use of interior insulation in the walls and double-glazed insulating glasses, often the stale air inside the houses, the increase in humidity and the poor ventilation of the rooms favors the proliferation of bacteria colonies developing on the comers between walls and ceilings the results in mold, that in a short time they spread in all the rooms of the house. There is thus a need to have an anti mold ability of the paint that guarantees the environment for a long time, even behind the furniture. Having a thermally insulating coating on the wall can reduce heat transfer from the exterior of a dwelling and the interior wall surface. While a limited number thermally insulating coatings exist, in many cases application of these coatings is limited to exterior surfaces. These coatings are not suitable for interior walls. Other prior art attempts have used solid ceramic beads, but these do not provide any thermally insulating properties.

[0007] In some construction, the thickness of slabs used to form walls, usually extruded polystyrene, can cause difficulties. While such slabs can provide guarantee an excellent design opportunities, they require additional thickness which, when added to the space already occupied by the frame that holds the panels, decrease the useful living space in the houses, which is undesirable. Furthermore, existing thermally insulating coatings remain difficult to apply, and are certainly not amenable to application by a typical consumer or homeowner.

[0008] Existing paints with anti-condensation and heat-insulating characteristics,

contain hollow microspheres which give the product a compact and light appearance similar to "meringue". As much as these paints can be mixed and reduced, when applying the coating with a roller, the high viscosity does not allow a homogeneous distribution of the product on the treated surface. This results in a creped and uneven appearance, such that a normal paint with added microspheres cannot be readily and satisfactorily applied. There thus remains a need for thermally insulating coatings that are suitable for interior application and that have physical properties making them simple to apply. Suitable thermally insulating coatings can also provide a reduction in condensation.

[0009] The present invention overcomes these and other problems in the prior art by providing, among other things, (1) long-term mold resistance, (2) in the rare cases where mold appears (for example in comers) it does not attach strongly to the paint and can be removed with a simple sponge soaked in water, and (3) ease of application of the paint as formulated, even for inexperienced painters such as consumers, which is superior to all existing formulations. BRIEF SUMMARY OF THE INVENTION

[0010] To overcome the problems in the prior art, embodiments of the present invention alter the Binder/Glass Bubble ratio. Traditional hollow microspheres are replaced with a smaller size type and the amount of binder in the formula is increased. In embodiments, the amount of surfactant is adjusted to avoid adding of water and lowering the dryness of the product. The invention achieves thermo-paint performance combined with ease of application.

[0011] Embodiments of the present invention lower the consistency of the final product, making it more easily distributed and homogeneous on the substrate softening the rough appearance.

[0012] The invention achieves optimization of the product, in terms of visual impact, by opening the bucket the product does not appear higher in consistency; under the application aspect, allowing the inexperienced consumer to easily apply the coating in the same manner as a normal water-based paint, all while preserving its anti-mold, anti condensation and heat-insulating performances.

[0013] In summary, the present invention is a coating composition for providing a

thermally insulating coating that includes a water dispersible polymer; an extender comprising calcium carbonate, and hollow glass spheres. In any embodiment, the hollow glass spheres can be soda-lime-borosilicate glass. In any embodiment, the hollow glass spheres have a thermal conductivity of about 0.07 W/m-K. In any embodiment, the hollow glass spheres have a density of about 0.22 g/cc and a pressure strength of about 28 bar. The water dispersible polymer can be a copolymer of vinyl acetate and vinyl esters of branched carboxylic acids. Coating compositions according to embodiments of the invention can include from about 8% to about 50% of a 50% water dispersion of the water dispersible polymer; from about 10% to about 20% of the calcium carbonate, and from about 5% to about 15% of the hollow glass spheres. In other embodiments, the composition can include from about 5% to about 15% of a 50% water dispersion of the water dispersible polymer; from about 10% to about 20% of the calcium carbonate, and from about 7% to about 12% of the hollow glass spheres. [0014] In any embodiment, composition also includes a pigment, which may be titanium dioxide. In any embodiment, the pigment may be about 5 to about 25% of the composition, or from about 5 to about 15% of the composition. In any embodiment, composition also includes at least one thickener. In any embodiment, the thickener can be methyl hydroxyethyl cellulose. In embodiments, the at least one thickener includes a low viscosity methyl hydroxyethyl cellulose having a viscosity of about 200 mPa*s and a higher viscosity methyl hydroxyethyl cellulose having a viscosity of about 10000 mPa*s. The composition can include from about 0.3% to about 0.5% of total thickeners. In any embodiment, composition also includes at least one additional extender. The at least one additional extender is a calcined clay, a silicate, or a Quartz-Barite powder. In any embodiment, composition also includes at least one preservative. In any embodiment, composition also includes one or more of a wetting agent, defoamer, emulsifmg agent, and dispersing agent.

[0015] According to the invention, a thermally insulating coating is prepared by

applying the composition of any embodiment of the invention to a surface and allowing the coating to dry or cure. The dried or cured coating prepared from a composition according to the invention can have a thermal conductivity of less than about 0.25 W/m- K, for example, a thermal conductivity of from about 0.10 to about 0.15 W/m-K, a thermal conductivity of about 0.123 W/m-K or about 0.07 W/m-K.

[0016] Compositions according to any embodiment of the invention can be applied by brushing, rolling or spraying.

[0017] Further objectives as well as the structure and function of embodiments of the invention will become apparent from a consideration of the description and examples.

DETAILED DESCRIPTION OF THE INVENTION

[0018] Embodiments of the invention are discussed in detail below. In describing embodiments, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected. While specific exemplary embodiments are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations can be used without parting from the spirit and scope of the invention. All references cited herein are incorporated by reference as if each had been individually incorporated.

[0019] In the description and examples that follow, all temperatures are set forth in uncorrected degrees Celsius unless noted otherwise. As used herein, the term "about" refers to plus or minus 10% of the indicated value. As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0020] Unless otherwise indicated, all parts and percentages are by weight. In setting forth weight percentages of components, the formulation should be considered to have about 44% water as a solvent. Persons skilled in the art may implement the invention using more or less water or solvent and the present description is intended to include such variations. The amount of other components can thus vary from what is disclosed herein based on the differing amount of water or solvent. For example, a component present in an amount of 10% in the present formulation would constitute about 17.9% of the non solvent composition (10% of component/56% total of non-aqueous components). Thus, in a composition having 50% water or solvent, the same composition contains about 8.95% of the component. Persons skilled in the art can readily calculate the total amount of a component when differing amounts of water or solvent are used. The teachings of the present disclosure thus include similar compositions where the exact amount of any particular component differs in a predictable way from that used in the exemplary embodiments described herein.

[0021] The present invention is directed to a coating, for example a paint, which

provides thermal insulation to the surface of a wall to which it is applied. The inventive coating provides energy savings, is highly durable, and can be applied safely and easily. The inventive coating can also reduce condensation on a wall’s surface and thus reduce mold. In embodiments, the coating includes anti-microbial components to further reduce or prevent the formation of mold. The coating exhibits reduced thermal expansion and shrinkage.

[0022] Use of thermally insulating coatings of the invention can also lead to reduced energy costs in a home in which the coating is applied to interior wall surfaces.

Particularly in harsh climates subject to high or low temperature extremes, heat transfer through walls can significantly contribute to energy costs by increasing the need for interior heating and cooling. That is, in cold climates, because loss of heat through exterior facing walls, it is necessary to use more energy to heat the interior of a dwelling. Similarly, in hot climates, heat transfer from the outside through the walls creates a need for increased cooling to maintain a particular interior temperature.

[0023] In cold weather, coating formed from the present invention protect the home by reducing heat loss through walls and ceilings. The thermal properties allow the home to maintain a comfortable temperature, avoiding unnecessary energy and economic waste. It also improves the insulating power of your home and effectively protects your walls and ceilings against mold growth.

[0024] In hot weather, the insulating power of coating formed from the present

invention allows the home to maintain a cooler, more comfortable temperature. Thanks to its formulation, it provides a thermal barrier that reduces cooling loss through walls and ceilings, improving energy efficiency. It also effectively protects walls and ceilings against mold growth.

[0025] Thus, by using a coating according to the present invention, additional insulating ability is provided beyond what may be installed during construction. Although difficult to quantify the exact savings, which will depend on factors such as the local climate, amount of sun and desired internal temperature, the thermal properties of coatings formed from the present invention (as described further below) can result in a significant energy savings, for example, a reduction of from about 5% to about 30%. Particularly in more extreme climates, energy savings of 10%-25% can be realized. In many cases, energy costs can be reduced by up to 20

[0026] The present invention achieves its thermal insulating and its physical properties allowing ease of application by including a water dispersible polymer, an extender that includes calcium carbonate, and hollow glass spheres. One problem with existing paints is that extenders and other components can greatly reduce thermal insulating properties, i.e. cause an increase in thermal conductivity. In particular, calcium carbonate which is a common extender, is known to be highly thermally conductive. Thus, while such components are desirable to provide coverage, opacity, and other properties making the coating easy to apply, when used in amounts typical of paints, especially those applied by consumers, the presence of these extenders and other components can greatly reduce any the thermal insulating properties of the coating. The present invention overcomes this difficulty of the prior art and advantageously allows the use of, for example, calcium carbonate. For example, a coating according to the invention can include about 10% to about 20% calcium carbonate, or about 15% to about 18% calcium carbonate, while maintaining a high thermal conductivity. Typically, embodiments of the invention may include about 15-16% calcium carbonate. Additionally, other extenders may also be present, as described further below.

[0027] The water dispersible polymer, which functions as the binder in the coating, can be any typical binder used in latex paints, for example, acrylic polymers and copolymers, styrene-acrylic copolymers, binders based on PVA polymers and copolymers, and others. While a range of binders are possible, the inventors have found that vinyl ester copolymers are particularly beneficial in providing improved stability and spreadability.

In some embodiments, the vinyl ester copolymer is a copolymer of vinyl acetate and vinyl esters of branched carboxylic acids. Exemplary vinyl esters of branched carboxylic acids used as monomers in binders of the invention are VeoVa™ Vinyl Esters available from Hexion (Columbus, OH). Exemplary copolymers of vinyl acetate and vinyl esters of branched carboxylic acids are sold under the tradename Ravemul, available from Vinavil S.p.A. (Milan, IT), for example Ravemul PC2. Binders are generally provided as an aqueous dispersion of about 50% polymer, and the aqueous dispersion may include other components, for example dispersing agents. The aqueous dispersion of binder may be present in an amount of from about 5% to about 50% of the formulation, for example, from about 8% to about 15% of the formulation or from about 10% to about 13% of the formulation.

[0028] The hollow glass spheres used in the invention can be similar to or in the form of 3M™ Glass Bubbles. 3M™ Glass Bubbles are hollow glass spheres made from soda- lime-borosilicate glass. Such glass bubbles have been used in a variety of formulations to provide thermal insulation. 3M™ Glass Bubbles have very low thermal conductivity (“K values,” measured as W/m-K) varying from, for example, about 0.044 W/m-K to about 0.187 W/m-K. By comparison the K value of calcium carbonate is about 3.9. The variety of 3M™ Glass Bubbles and associated properties are shown in Table 1.

Table 1. Typical Physical Properties of 3M™ Glass Bubbles

* Minimum 90% survival at specified pressure

** @ 20°C

[0029] However, use of 3M™ Glass Bubbles in paints, particularly latex paints, has not been previously obtained in a suitable formulation. Prior attempts to produce a paint with properties suitable for application by a consumer that also have low thermal conductivity and high opacity have not been successful. All paints with anti-condensation and heat- insulating characteristics, contain hollow microspheres which give the product an unacceptably compact and light appearance. Although various mixtures reduce this negative aspect, when applied with a paint roller, the high viscosity does not allow homogeneous distribution of the product, resulting in a creped and uneven appearance. Accordingly, it is not possible to simply add glass microspheres, such as existing of 3M™ Glass Bubbles, to a standard formulation and achieve a coating that can be applied in a normal manner.

[0030] To overcome this negative impact, the present invention varies the formulation, such as the Binder / Glass Bubble ratio. For example, traditional hollow microspheres can be replaced with a smaller size type and the amount of binder in the formulation can be increased. In addition, the amount of surfactants is varied to avoid adding water and lowering the dryness of the product. By varying these constituents as set forth herein, a thermal paint with enhanced performance is achieved. According to embodiments, by lowering the consistency of the final product, it is distributed homogeneously and easily on a substrate and the normally rough appearance is softened.

[0031] The result of the invention is that upon simply opening the container, the

product does not appear higher in consistency and is easily applied by the inexperienced consumer as a normal water-based paint, all while preserving its anti-mold, anti condensation and heat-insulating performances.

[0032] A particularly advantageous type of 3M™ Glass Bubbles for use in the present invention is the type designated S22. The hollow glass spheres can be used in formulations according to the invention in amounts from about from about 5% to about 15%, from about 7% to about 12%, or from about 8.5% to about 10.5%, or about 9.25%.

[0033] Thermal conductivity is a measure of the temperature transfer capacity of a material. Normal paints, provide a thermal conductivity of from about 0.3 W/m-K to 0.5 W/m-K or typically about 0.340 W/m-K, but can be higher. In contrast, formulations according to the invention produce, upon curing, coatings with much lower thermal conductivity. Typical paints can have thermal conductivities in the order of. In contrast, coatings prepared from formulations according to the present invention can have thermal conductivities less than 0.25 W/m-K. Exemplary embodiments can have thermal conductivities of less than 0.15 W/m-K, for example, about 0.123 W/m-K. In embodiments, coatings prepared from the inventive formulations can have thermal conductivities on the order of 0.07 W/m-K.

[0034] Coatings formed from the present composition show additional advantageous thermal properties. For example, a measure of heat transfer through a coating of the invention shows a smaller temperature rise upon exposure to solar radiation. This difference in temperature rise can be, for example, about 1°C or more after 20 min of solar radiation exposure (at Temp=35°C and RH%=60%). In addition, the thermal properties if the coatings can have an increased anti-condensation capacity, as measured by water retention per unit area, even when compared to an existing paint claiming anti condensation properties. Anti-condensation capacity measures the ability of a coating to superficially retain water that condenses on the walls or ceiling during cooling periods, typically during the night. During the day and during the periods of the material heating, the release of the water retained by evaporation takes place almost completely. If the water is not retained, condensation occurs and water drips and accumulates, making re evaporation more difficult. Existing paints, even those claiming anti-condensation properties can have a water retention of less than 70 g/m², for example about 67.4 g/m². In contrast, coatings formed by the present invention typically have a water retention of less than 70 g/m², for example about 72.6 g/m². This higher water retention prevents condensation.

[0035] Formulations of the invention also include water or another solvent. Water can be present in amounts ranging from about 25% to about 75%, from about 30% to about 50% of about 44-45%. As stated above, that amounts of the various components set forth in this description assume a water content of about 44%. Formulations using different amounts of water will vary in the amounts of other components, but are readily adjustable based on the present disclosure. Formulations with differing amounts of components provided simply by adjusting the amount of solvent are well within the scope of the teachings herein.

[0036] In addition to the water dispersible polymer, calcium carbonate and hollow glass spheres, coatings according to the invention can include additional component typically used in paints. Typical additional components include, for example, pigments, thickeners, fillers, extenders, dispersing agents and surfactants, wetting agents, defoamers, and preservatives. Persons skilled in the art will be familiar with typical components and, based on the disclosure herein, substitute alternative compositions for those explicitly described herein. While many ingredients that serve similar functions can be used interchangeably, due to the inherent difficulties in formulating a product with suitable physical and thermal properties, at times there are preferred ingredients or combinations of ingredients, and those are identified and described herein. Based on the present teachings, persons skilled in the art may be able to develop formulations with alternative ingredients and these are intended to be within the scope of the invention.

[0037] Formulations according to the invention can further include one or more

pigments. An exemplary pigment is titanium dioxide (TiC ). Titanium dioxide provides excellent opacity and imparts a white color to the coating. In some cases, the calcium carbonate, as well as other extenders and thickeners, can function as pigments. As identified herein, the amount of pigment does not include other components that are added primarily as fillers, extenders, or for some other purpose. Embodiments of the invention can include, for example, from about 5% to about 25% pigment, or from about 5% to about 15% pigment. Formulation as described herein can be considered a base formulation. As is well known in the art, a base formulation is generally a white or light colored paint or coating that can be tinted or colored as desired by the addition of additional pigments and coloring agents. The use of such pigments and coloring agents in addition to the pigments specifically described here are contemplated by the invention, with the realization that adding such pigments could slightly affect, i.e. cause a reduction in, the amounts of the described components of the formulation.

[0038] Formulations according to the invention can further include one or more

thickeners. In principal, any conventional thicker can be used, for example, clays, cellulosics (for example, carboxy methylcellulose (CMC), hydroxymethylcellulose (HMC), hydroxypropyl methylcellulose (HPMC), non-ionic methyl hydroxyethyl cellulose (MHEC), and etherified derivatives thereol), gums, sulfonates, and silicates, such as hydrated magnesium silicate, and oraganosilicones. Thickeners are typically added in a total amount of from about 0.1 to about 10% of the formulation, for example, from about 0.1 to about 1% of the formulation, or from about 0.3% to about 0.5% of the formulation. When more than one thickener is used, any individual thickener may be present in an amount of less than 0.1 %. It has been found that the use of a mixture of non ionic MHECs provides a formulation with excellent viscosity and water retention, and help in providing physical properties that make the paint more spreadable and easy to apply. In particular, use of a low viscosity MHEC, for example having a viscosity of about 200 mPa*s. in combination with a high viscosity MHEC, for example having a viscosity of about 10000 mPa*s. has been found to be particularly advantageous. Examples of suitable MHECs are available under the tradename Tylose® MH from SE Tylose GmbH & Co. KG (Wiesbaden, DE). Other suitable non-ionic methyl hydroxyethyl cellulose materials, as well as other celluolosics with similar viscosities and other properties and attributes can also be used. When a mixture of low viscosity and high viscosity non-ionic methyl hydroxyethyl cellulose is used, the formulation can include, for example, about 0.002% of a non-ionic methyl hydroxyethyl cellulose with a viscosity of 200 mPa*s and about 0.33% of a non-ionic methyl hydroxyethyl cellulose with a viscosity of about 10000 mPa^»s.

[0039] Formulations according to the invention can further include one or more

extenders in addition to the calcium carbonate. Additional extenders can include, for example, a calcined clay, a silicate, or Quartz-Barite powder. Additional extenders may be present in an amount of from about 1% to about 10%, or from about 3% to about 7% of the formulation, in addition to the calcium carbonate.

[0040] Formulations according to the invention can further include one or more

preservatives, which may be, for example, a biocide, an antibacterial, an antimicrobial, or an antifungal. Preservatives used in formulations of the invention can help preserve the aqueous paint during storage and/or provide further protection against the development of molds and fungi on the coated surface. Exemplary preservatives can include zinc pyrithione, carbendazim, octilisotiazolinone, chloromethyl isothiazolinones, methyl isothiazolinones, benzisothiazolinones, and combinations thereof. Preservatives providing storage stability can include: chloromethyl isothiazolinones, methylisothiazolinones and benzisothiazolinones. Preservatives (i.e. biocides) that provide anti-mold properties can include zinc pyrithione, octilisotiazolinone, carbendazim and combinations thereof.

[0041] The amount of preservatives present individually are limited to quantities

dictated by regulations in various jurisdictions and need not be exceeded. The actual amount may vary depending on the concentration of other active ingredients. Preferably the amounts are close to the maximum amounts allowable by local regulations.

Accordingly, preservatives may be individually present in amounts of from about 0.05% to about 1%, and collectively present in an amount totaling from about 0.5% to about 2.5%.

[0042] Formulations according to the invention can further include one or more wetting agents, defoamers, surfactants, emulsifying and dispersing agents, and coalescing agnets. Exemplary wetting agents include cationic, anionic and non-ionic wetting agents. Specific wetting agents include polyglycol esters, saturated and unsaturated fatty acids, monoethylene glycol, and mixtures thereof. Polyether siloxane copolymers are typical defoamers (or anti foaming agents) although others are known and can be used. Surfactants, emulsifying and dispersing agents can include, for example, derivatized acrylic copolymers (for example Dysperbyk 2010, available from BYK-Chemie GmbH, Sesel, DE), anionic dispersents, (such as anionic poly acrylates), and monosodium phosphate monohydrate. Coalescing agents include ester alcohols (for example Texanol™ available from Eastman Chemical Company (Kingsport, TN), and monoethylene glycol (which can also act as a wetting agent). Finally, an alkalizing agent, for example sodium hydroxide or an aqueous solution of sodium hydroxide, can be added to adjust the formulation to a desirable pH. Persons skilled in the art will recognize and be able to identify additional alternatives for these specific ingredients.

EXAMPLES

[0043] The invention is further exemplified by the non-limiting examples that follow:

EXAMPLE 1 - Exemplary Formulation

[0044] An exemplary coating according to the invention was prepared with the components set forth in Table 2. Examples of commercially available components that have been found to, in combination, provide the described desirable thermal and application properties of the invention are identified as exemplary.

TABLE 2. Composition of Exemplary Formulation

[0045] EXAMPLE 2 - Thermal Conductivity Testing

[0046] The thermal conductivity of a paint prepared according to the composition

shown in Example 1 was compared to a standard paint formulation.

[0047] Method

[0048] Thermal conductivity was measured with a TCi Thermal Conductivity Analyzer in accordance with ASTM D7984 - 16 Standard (“Test Method for Measurement of Thermal Effusivity of Fabrics Using a Modified Transient Plane Source (MTPS) Instrument.”)

[0049] The default C-Therm TCi Thermal Conductivity Analyzer employs the Modified Transient Plane Source (MTPS) technique in characterizing the thermal conductivity and effusivity of materials. It employs a one-sided, interfacial heat reflectance sensor that applies a momentary constant heat source to the sample. Samples were applied at a thickness of 5 mm and allowed to dry for 48 hours at 40°C before measurement. In all cases the sensor ID was T185.

[0050] Table 3 shows the results of measurements for the inventive composition. Table 4 shows the results for a standard paint formulation.

Table 3. Thermal Conductivity of Inventive Composition

Table 4. Thermal Conductivity of Standard Paint

[0051] The thermal conductivity of the inventive composition was determined to be about 0.070. The first two measurements in Table 4 seem to be outside the norm and are not considered as reliable. The thermal conductivity of the standard paint was determined to be about 0.340.

[0052] EXAMPLE 3 - Infrared Thermography Scanning

[0053] The qualitative measurement of infrared thermography scanning on an inventive composition of Example 1 was compared to a standard commercial paint.

[0054] Method

[0055] Infrared thermography scanning was performed using an Agema ERIKA

Thermal camera. The scanning images were obtained using two samples of 5 mm thickness and 80 mm of diameter. The samples were exposed outside for 10 min of solar radiation; emissivity value = 0.9 for each sample analyzed. During the infrared scanning, a part of sample about 5x5 cm² of area was used. The scanning analyzed an area on the sample about 1 cm². Samples were applied at a thickness of 5 mm and allowed to dry for 24 hours at 40°C before measurement. Measurement of the temperature difference began after steady-state conditions were reached.

[0056] Results are shows in Table 5.

Table 5 - Results of Infrared Thermography Scanning

[0057] Based on image analysis, a temperature difference of about 1°C was observed between the inventive composition and a standard commercial paint after 20 min of solar radiation exposure (Temp=35°C- RH%=60%).

[0058] EXAMPLE 4 - Anti-Condensation Capacity

[0059] The anti-condensation capacity of the inventive composition was measured and compared with a standard commercial paint. The test assessed the ability of a coating to superficially retain water that condenses on the walls or ceiling during cooling periods, typically during the night. During the day and during the periods of the material heating, the release of the water retained by evaporation takes place almost completely. In contrast, if the water is not retained, it begins to drip and accumulate in some areas, making re-evaporation more difficult.

[0060] Method

Method: Nordtest method NT Poly 170

Instrument: Climatic chamber Controls mod. 10-D1428/A with temperature and humidity control. Cylindrical SS support with a conical bottom cooled internally with a mass of ice has been used for water condensation on paints.

Test conditions: 23 °C, 50% RH in the chamber, 0 °C on the sample holders

No of samples tested: four / sample paint to analyze

Average amount of applied paint: Sample A = 284.8 g/m²; Sample B = 292.2 g/m²

Average amount of dry paint applied: Sample A = 170.9 g/m²; Sample B = 143.1 g/m² Measured parameters:

• Water retention per unit of surface = amount of water retained on the measuring cone in stationary condensation conditions expressed in g/m²

• WPAC = percentage measurement of the amount of water retained referred to the amount of applied wet paint.

[0061] Table 6 shows the results of measurements for the inventive composition. Table 7 shows the results for a standard paint formulation

Table 6. Anti-Condensation Capacity of Inventive Composition

Table 7. Anti-Condensation Capacity of Inventive Composition

[0062] Based on the data collected by testing a wide range of commercial acrylic paints available on the market, an evaluation scale was developed by the testing laboratory (Salentec srl (Lecce, IT) articulating three degrees of effectiveness of the anti condensation capacity based on the quantity of water retained per unit area:

A (Most effective) >70 g/m²

B (Average effectiveness) >42 g/m² e <70 g/m²

C (Ineffective) <42 g/m²

Based on these data, the inventive composition was shown to have a higher anti condensation capacity as compared to commercial paints.

[0063] The embodiments illustrated and discussed in this specification are intended only to teach those skilled in the art the best way known to the inventors to make and use the invention. Nothing in this specification should be considered as limiting the scope of the present invention. All examples presented are representative and non-limiting. The above-described embodiments of the invention may be modified or varied, without departing from the invention, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that, within the scope of the claims and their equivalents, the invention may be practiced otherwise than as specifically described.

Claims

WHAT IS CLAIMED IS:

1. A coating composition for providing a thermally insulating coating comprising:

a water dispersible polymer;

an extender comprising calcium carbonate, and

hollow glass spheres.

2. The coating composition of claim 1, wherein the water dispersible polymer is a copolymer of vinyl acetate and vinyl esters of branched carboxylic acids.

3. The coating composition of claim 1, comprising:

from about 8% to about 50% of a 50% water dispersion of the water dispersible polymer;

from about 10% to about 20% of the calcium carbonate, and

from about 5% to about 15% of the hollow glass spheres.

4. The coating composition of claim 1, comprising:

from about 5% to about 15% of a 50% water dispersion of the water dispersible polymer;

from about 10% to about 20% of the calcium carbonate, and

from about 7% to about 12% of the hollow glass spheres.

5. The composition of claim 1, further comprising a pigment.

6. The coating composition of claim 5, wherein the pigment is titanium dioxide.

7. The coating composition of claim 5, wherein the pigment comprises from about 5 to about 25% of the composition.

8 The coating composition of claim 7, wherein the pigment comprises from about 5 to about 15% of the composition.

9. The coating composition of claim 1, further comprising at least one thickener.

10. The coating composition of claim 9, wherein the at least one thickener comprises methyl hydroxyethyl cellulose.

11. The coating composition of claim 9, wherein the at least one thickener comprises a low viscosity methyl hydroxyethyl cellulose having a viscosity of about 200 mPa*s and a higher viscosity methyl hydroxyethyl cellulose having a viscosity of about 10000 mPa^»s

12. The coating composition of claim 9, comprising from about 0.3% to about 0.5% of total thickeners.

13. The coating composition of claim 1, further comprising at least one additional extender.

14. The coating composition of claim 13, wherein the at least one additional extender is a calcined clay, a silicate, or a Quartz-Barite powder.

15. The coating composition of claim 1, further comprising at least one preservative.

16. The coating composition of claim 1, further comprising one or more of a wetting agent, defoamer, emulsifmg agent, and dispersing agent.

17. The coating composition of claim 1, wherein the dried composition provides a thermal conductivity of less than about 0.25 W/m-K.

18. The coating composition of claim 1, wherein the dried composition provides a thermal conductivity of from about 0.10 to about 0.15 W/m-K.

19. The coating composition of claim 1, wherein the dried composition provides a thermal conductivity of about 0.123 W/m-K or about 0.07 W/m-K.

20. A thermally insulating coating prepared by applying the composition of claim 1 to a surface and allowing the coating to dry.

21. The coating of claim 20, having a thermal conductivity of less than about 0.25 W/m-K.

22. The coating of claim 20, having a thermal conductivity of less that about 0.15 W/m-K.

23. The coating of claim 20, having a thermal conductivity of about 0.123 W/m-K or about 0.07 W/m-K.

24. The coating of claim 20, wherein the applying comprises brushing, rolling or spraying.