WO2015179476A1 - Lightweight spackling paste composition containing hydrated silica - Google Patents

Abstract

Embodiments of spackling and similar compounds that include hydrated silica as low-density filler are provided. Various forms of hydrated silica, particle sizes, and specific gravities, are used to generate compositions exhibiting a wide range of properties, which may include thermal insulative properties, mass density properties, and smoothness. Other additives may be included to enhance thermal properties and mass density properties, as well as modify light reflective properties, opacity, and color. Embodiments may be used to correct defects within interior and exterior construction surfaces and/or prepare surfaces for an additional coating. Other properties of the hydrated silica composition are used to increase yield and improve work-place safety when working with the composition.

Description

LIGHTWEIGHT SPACKLING PASTE COMPOSITION

CONTAINING HYDRATED SILICA

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims the benefit of co-pending U.S. Provisional Patent Application No. 62/000,716 filed on May 20, 2014, which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] Field of the Invention

[0003] The present invention is directed to the use of hydrated silica as low-density filler to produce lightweight spackling and similar compounds, and in particular using hydrated silica as a low density filler to enhance thermal and mass density properties of such compounds.

[0004] Background of the Related Art

[0005] Carbonate rocks, such as limestone and dolomite, are commercialized worldwide. Calcareous sedimentary rocks are composed mainly of calcite (CaCO₃), which has an average specific gravity 2.72 g/cm . Dolomites, which are sedimentary rocks, are composed primarily of the mineral dolomite (CaCO₃ MgCO₃), which has an average specific gravity 2.86 g/cm . A common practice is to include the use of these mineral as filler in compounds, such as construction material compounds, air purification compounds, paper coatings, plastics, paints, ceramics, etc. A particular use of calcite and dolomite commonly used in the art is that of fillers in the production of heavy-duty putties (e.g., spackling) and mastic compositions (e.g., paint).

[0006] Heavy-duty spackling paste is used in construction and related applications to cover facade structures (e.g., drywall, wood, plaster, etc.), concealing defects and generating an aesthetically appealing surface to the facade structure. Unfortunately, conventional spackling has a high mass density, which renders its use arduous, especially when the situation dictates a large amount of the spackling to be used. In other words, working with large amounts of spackling and carrying containers of conventional spackling is unwieldy while attempting to spackle a facade structure because of its high mass density. Additionally, the high mass density of conventional spackling requires containers holding the spackle to support relatively heavy loads, which may add to the overall cost of the spackling compound, not to mention contributing to a general waste of resources that could be avoided if the spackling compound existed at a lower mass density. Another disadvantage of conventional spackling is the lack of dual functionality. Conventional spackling attempts to serve a single purpose of concealing defects, and does little else to provide other benefits, such as thermal insulation for example. The same challenges and disadvantages apply to conventional heavy-duty paints.

[0007] One of the disadvantages associated with conventional heavy-duty spackling and paints is their reliance on calcite, dolomite, and similar materials as fillers within the composition of the spackling and/or paint compounds. These fillers are heavy. Like all mineral rock, calcite and dolomite have, as impurities in their composition, various types of clays, sulfides, sulfates, phosphates and iron, which may further add to the costs of using such materials. Moreover, producers of these materials typically have little or no control over properties such as average volume, average pore size, average particle size, oil absorption, and average surface area.

BRIEF SUMMARY OF THE INVENTION

[0008] Silicon dioxide ("silica") is the most common binary compound of silicon and oxygen, which are the two elements of greatest terrestrial abundance. Silica may be a fundamental material of glass, ceramic, and refractory material, as well as the raw material for the production of soluble silicates, silicones, and other silicon-based chemicals. Used as low- density filler, it may exhibit properties that open new possibilities for alternatives to the use of calcite, dolomite, and other conventional heavy-duty fillers used in spackling, putties, pastes, paints, and similar compounds. Some of the benefits of using silica as a filler within such compounds may include, but are not limited to, lower mass density, ease of application of the compounds, increased heat insulative and light reflective properties, and reduction of production and shipping costs. Such benefits are long sought by manufacturers, suppliers, retailers, and end users of these compounds.

[0009] In its amorphous form, silica may be used as a desiccant, adsorbent, reinforcing agent, filler, and/or catalyst component for innumerous compounds, such as paints, synthetic resins, plastics, rubbers, cosmetics, nutritional products, drugs, etc. As by way of example, amorphous silica may be synthesized by acidifying a relatively concentrated aqueous solution of sodium silicate. Using techniques common in the art, amorphous silica may be obtained in powder form with a high degree of purity (e.g., low levels of impurities and low levels of crystalline structure). For example, BRITESORB^® A100 brand silica (hydrogel type) is one commercially available amorphous silica that may be used in embodiments of the invention. In that silica, we control iron (maximum 50 ppm), water soluble salts (maximum 5% by weight) and heavy metal as lead (maximum 10 ppm), all of which are present as impurities. Typical Properties of BRITESORB^® A100 are: Si0₂ (1000 °C, 2 hours) > 94%; pH (12% water slurry) = 3; Surface area = 770 m /g; Loss on drying @ 105°C = 61 %; and Median particle diameter = 16 μιη. [0010] Other types of silica may include, but are not limited to, precipitated silica, hydrogel silica, sol-gel silica, fumed silica, and/or aerogel silica, which may be amorphous silica, hydrated silica, synthetic silica, anhydrous silica, xerogel silica or any combination thereof.

[0011] Using hydrated silica we are able to provide a spackling composition including about 25% by weight of solid contents (ignited based on 1000°C, 2 hours), as shown in Composition I, below. Further embodiments include solid compounds between 20-30%, 15-25%, 20-30%, 25- 35%, 25-40%, and 25-50%. These compare favorably with prior compositions that might include 60% or more of solids content, as reported below.

[0012] Using hydrated silica (e.g., XSi0₂ YH₂0) as a filer may generate a spackling compound

3 3 having an average specific gravity between the ranges of 0.1-2.5 g/cm , 0.2-2.5 g/cm , 0.3-2.5 g/cm³, 0.4-2.5 g/cm³, 0.5-2.5 g/cm³, 0.6-2.5 g/cm³, 0.7-2.5 g/cm³, 0.8-2.5 g/cm³, 0.9-2.5 g/cm³, 1.0-2.5 g/cm³, 1.1-2.5 g/cm³, 1.2-2.5 g/cm³, 1.3-2.5 g/cm³, 1.4-2.5 g/cm³, 1.5-2.5 g/cm³, 1.6-2.5 g/cm³, 1.7-2.5 g/cm³, 1.8-2.5 g/cm³, 1.9-2.5 g/cm³, 2.0-2.5 g/cm³, 2.1-2.5 g/cm³, 2.2-2.5 g/cm³,

3 3

2.3-2.5 g/cm , and 2.4-2.5 g/cm . For example, a spackling compound including a single inorganic hydrogel amorphous silica (e.g., Britesorb® A 100 made by PQ Corporation, USA) may have an average specific gravity as low as 1.1 g/cm . This is a considerable improvement over prior art, which exhibits an average specific gravity of 1.7 g/cm and average solid content of 60% by weight (e.g., Massa Corrida Coral® from AkzoNobel, Maua, SP, Brazil and Suvinil Massa Corrida® from BASF, S.B. Campo, Brazil). Some prior art spackling purports to exhibit an average specific gravity of 1.3 g/cm with a total solid content of 57% by weight (e.g., Super Leve® from Anjo Tintas, Santa Catarina, Brazil), which is still far above 1.2 g/cm . One reason the prior art spackling compounds exhibit such high specific gravities is because they typically use a higher percentage of more dense fillers (e.g., calcite or dolomite), such as the spackling compound reported in United States Patent No. 7,790,796 B2.

[0013] In addition to low specific gravity, a relatively large amount of water may be held in mixture with hydrated silica at room temperature, due to the molecular polarity of water, to form low density hydrated silica liquid, paste, and/or putty compound. The resultant compound may include a range of water content from 1-90% by weight. As described herein, changing the relative content levels of water and hydrated silica may be done to generate material and workability properties desired for a particular application. Hydrated silicas may have a silica to water mass ratio of 0.1-99.9% silica to 0.1-99.9% water.

[0014] Other additives may be included with the hydrated silica composition. These may include, but are not limited to, ancillary low-density filler agents, resin binder agents, pigment agents, thickener agents, emulsion agents, plasticizer agents, dispersant agents, defoamer agents, alkalizing agents, preservative agents, anti-corrosive agents, coalescing agents, solvents (in addition to or in the alternative to water), and other conventional additives used for production of spackling and similar materials. Generally these may make up 30-75% by weight.

[0015] As disclosed herein, such compositions may be used to generate compounds for spackling, putty, paint, and/or similar coatings that exhibit properties far beyond merely concealing defects and coating a surface. A spackling compound comprising a mixture including hydrated silica may exhibit light reflective properties, thermal insulative properties, and low mass density properties that far exceed those of prior art spackling compounds, which may be desirous for a wide range of applications. Different mixtures will exhibit different properties, which may be used to engineer a mixture best applicable to a particular application. [0016] For example, some hydrated silica spackling compositions may exhibit enhanced thermal insulative properties in addition to having a lower mass density. As another example, some hydrated silica spackling compositions may demonstrate quicker drying times, as compared to prior art spackling compounds due to the lower percentage of low density fillers (e.g., hydrated silica). This was determined by comparing a spackling composition as newly reported herein with a composition including calcite in lieu of hydrated silica. The calcite composition dried much more slowly.

[0017] The hydrated silica composition may also exhibit a smaller shrinkage effect upon drying. Other properties that may be modified may include, but are not limited to, specific density, specific gravity, scrub resistance, resistance to corrosion (salt, weather, alkalinity, etc.), acoustic properties, and other material properties such as strength, hardness, opacity, color, etc. Hydrated silica spackling compounds (like that of Composition I, below) may dry in 15 minutes when heavy duty spackling paste dries after 30 minutes. Data were observed when applied both compounds over a concrete wall surface, applied in a 2 mm thickener, exposed at 25°C and 70% of relative humidity. The drying time was measured by touching the surface with a finger and it was considered dried when it had no sticky effect, evaluated for a qualified worker. Generally, the drying time may be influenced by the amount of water, fillers, additives and the solvents, like turpentine, in its composition.

[0018] Some producers of prior art compounds attempt to generate lower density compounds by using glass, plastic, or ceramic microspheres as fillers. These fillers are much more expensive than hydrated silica, and they still fail to generate the above-referenced and unexpected material properties that hydrated silica generates. [0019] Applications of the hydrated silica compositions disclosed herein range from covering interior and exterior walls, doors, floors, ceilings, roofs, etc. These structure may comprise concrete, wood, drywall, gypsum board, plaster, metal (e.g., galvanized steel plate roofing), fibroconcrete, ceramic, plastic, etc. In addition, the hydrated silica compositions may be created in powder form, liquid form, in paste form, and/or putty form. The ability to exist in many forms enables applying the hydrated silica compositions in various ways, such as brushing, rolling, spraying, and/or spreading with a knife or trowel onto an ancillary surface. Any of these application methods may be performed manually or by machine.

[0020] While these potential advantages are made possible by technical solutions offered herein, they are not required to be achieved. The presently disclosed compounds and methods can be implemented to achieve technical advantages, whether or not these potential advantages, individually or in combinations, are sought or achieved.

BRIEF DESCRIPTION OF THE FIGURES

[0021] Not applicable.

DETAILED DESCRIPTION OF THE INVENTION

[0022] The following description is of an embodiment presently contemplated for carrying out the present invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles and features of the present invention. The scope of the present invention should be determined with reference to the claims.

[0023] In composition, the hydrated silica (along with the other constituent parts) forms a compound, which is referred to herein as the hydrated silica composition. In composition, the hydrated silica acts as low-density filler for the compound. However, the hydrated silica may also be utilized to generate other properties in addition to being low-density filler. While exemplary embodiments describe hydrated silica compositions for use as spackling compounds, it is understood that the various embodiments of the hydrated silica compositions may be used to generate paste, putty, paint, and/or similar coatings.

[0024] Other additives may be used to further modify the above-mentioned properties in addition to hydrated silica. However, it should be noted that some additives used as a component of the compound may compromise the low density and insulative properties of the hydrated silica composition. Additives that enhance low density and insulative properties may be preferred.

[0025] The hydrated silica composition may include a hydrated silica component, hydrogel type as preferred silica, and a solvent. The solvent may include water, preferably. Additional components may be added to the hydrated silica composition. These may include, but are not limited to, ancillary low-density filler agents, resin binder agents, pigment agents, thickener agents, emulsion agents, plasticizer agents, dispersant agents, defoamer agents, alkalizing agents, preservative agents, anti-corrosive agents, coalescing agents, solvents (in addition to or in the alternative to water), and other conventional additives used for production of spackling and similar materials. Any component, additive, and/or the resultant hydrated silica composition may exist in powder form, liquid form, paste form, and/or putty form. Additionally, any component and/or additive may be water soluble, oil soluble, natural, synthetic, or any combination thereof.

[0026] Hydrated silica component

[0027] Hydrated silica may be present with a particle size distribution (PSD) D50 within ranges from 0.1-100 microns, 1-70 microns, and 5-30 microns in an amount ranges from 1- 95% by weight, 10 - 80% by weight, 20-70% by weight, 30-60% by weight, 35-45% by weight, and 30-50% by weight, wherein a PSD D50 range from 5-30 microns and amount range from 30- 50% by weight are preferred. The PSD and amount by weight percent may be changed to obtain a desired smoothness and workability to the resultant hydrated silica composition. For example, a PSD D50 range from 5-30 microns and 30-50% by weight may generate a very smooth hydrated silica composition, whereas a PSD D50 higher than 100 microns may generate a coarse hydrated silica composition for a more rustic look. The hydrated silica component may exist with a specific gravity within a range from 0.1 g/cm 3 to 2.5 g/cm 3.

[0028] The hydrated silica used at in compositions that are embodiments of the invention may have additional features besides PSD. The preferred hydrogel silica used (BRITESORB® A100) has an average surface area of 700 m7g maximum. Hydrated silicas with surface area above 700 m 2 /g are also suitable for this use. For example, a surface area between 650-800 m 27g may be used.

[0029] The preferred pH of hydrated silica is alkaline when dispersed in water, although an acid pH of a hydrated silica may also be useful for this application, as the acid pH of A100. The preferred hydrogel silica, A100 type, has also oil absorption of 80 g/lOOg (linseed oil) maximum. Above 80 g/lOOg (linseed oil) are also suitable for the use. For example, 90g/100g may be used, though attention should be paid regarding the final viscosity of compositions and to avoid too great of an oil absorption. The water content lost by ignition (1000 °C, 2 hours) of A100 is controlled to be 80% by weight maximum. Above 80% may also be used for this application. The higher the water content, lower the density of the hydrated silica, where the closer it approaches the density of water the better the performance is for the compositions.

[0030] Solvent component [0031] Embodiments of the invention may include water as a main solvent. Including water in the compound may decrease volatile organic content and may be considered composition. Water-based compositions are preferred and comprises water from 10-90% by weight, preferably from 60-80% by weight, based on the total weight of solids on compounds. Other polar or nonpolar, inorganic or organic solvents (e.g., turpentine), which may be water or oil soluble may be used in addition, or in the alternative, to water. Solvents may be present in amount ranges from 0.01-90% by weight, 5-80% by weight, and 20-60% by weight, wherein 20-60% by weight is preferred. Solvents may add special features to the compound and may be also considered as additives. They may influence the performance of a compound, like drying time, odor, consistency and applicability. As an example, turpentine may be used to increase the time that a compound dries in order to keep it pliable during application, allowing reworking prior to completely dries, specially preferred or used when warm environments accelerate the

evaporation of a water-based composition, as an example.

[0032] Ancillary low-density filler component

[0033] Ancillary low-density filler components may be used in addition, or in the alternative, to hydrated silica components. These ancillary low-density filler components may exhibit an average specific gravity lower than that of calcite or dolomite, preferably. Thus, addition of ancillary low-density fillers may be used to further reduce the specific gravity of the compound. An example of ancillary low-density fillers may include, but are not limited to, clays, zeolite, glass bead, ceramic, plastic, wax, rubber, calcium based additives, etc. Ancillary low-density filler components may be present in amount ranges from 0.1-40% by weight, 1-30% by weight, and 5-10% by weight, wherein 5- 10% by weight is preferred.

[0034] Resin binder component [0035] Selection of the type and amount of binder may depend on the application of the hydrated silica composition (e.g., indoor or outdoor, type of surface to be applied to, ambient temperature during application, etc.). Resin binders may include, but are not limited to, organic and/or inorganic polymers, vinyl acetate, styrene acrylic, vinyl acrylic, acrylic, silicate, etc. An example of resin binder that may be used is RA 193 by Denver Especialidades Quimicas - Resinas of Sao Paulo, Brazil, which is an aqueous dispersion of styrene acrylic copolymer. Resin binder components, as dry solid content, may be present in amount ranges from 0.1-20% by weight, 1- 10% by weight, and 2-7% by weight, wherein 2-7% by weight is preferred.

[0036] Pigment components

[0037] Pigment components may be any agent that imparts a color to the hydrated silica composition. Pigments may include, but are not limited to, carbon black, titanium dioxide, etc. Pigment components may be present in amount ranges from 0.01-95% by weight, 0.03-30% by weight, and 0.05-10% by weight, wherein 0.05- 10% by weight is preferred.

[0038] Thickener component

[0039] Thickener components may be added to modify consistency for a desired application. Examples of thickener components may include, but are not limited to, cellulose derivatives, cornstarch, xanthan gum, mineral clay derivatives, organic/inorganic-modified mineral clays, acrylic or urethane polymers, synthetic associative thickeners, etc. Specific examples of thickener components that may be used are Latekoll® BA 800 and Rheovis®PE1331, both by BASF of Brazil. Thickener components may be present in amount ranges from 0.1-15% by weight, 0.2-7% by weight, and 0.3-5% by weight, wherein 0.3-5% by weight is preferred.

[0040] Emulsion component [0041] A water-soluble emulsion and/or a hydrophobic component may be added to modify water repellency and water absorption related to the principal filler used (e.g., hydrated silica). Emulsion and/or hydrophobic components may include, but are not limited to, colloids (e.g., paraffin emulsion, natural or synthetic waxes emulsion, silicone emulsions, fluorine-based polymers emulsion, etc.) and fluor compounds (organic and/or inorganic). A specific water- soluble paraffin emulsion that may be used is Arpel PA450 by Arzu Ind. e Com. of Sao Paulo, Brazil. Emulsion components may be present in amount ranges from 0.1-10% by weight, 0.5- 7% by weight, and 1-5% by weight, wherein 1-5% by weight is preferred.

[0042] Plasticizer component

[0043] Plasticizer components may be added to modify the plasticity of the hydrated silica composition. Plasticizers may include, but are not limited to, plastics, rubber, concrete, clays, glycols, polyethers, organophosphates, sulfonamides, polybutene, glycerides, alkylcitrates, organonitrates, adipates, sebacates, maleates, dicarboxylic/tricarboxylic ester-based, trimellitates, etc. A specific example of a plasticizer that may be used is diisobutyl phthalate (DIBP) by Elekeiroz of Brazil. Plasticizer components may be present in amount ranges from 0.1-20% by weight, 0.5- 10% by weight, and 3-7% by weight, wherein 3-7% by weight is preferred.

[0044] Dispersant component

[0045] A dispersant component may be used to increase the dispersion efficiency of fillers so as to avoid propensities of sedimentation/flocculation that often result from the natural tendency of fillers to agglomerate. The dispersing agent may be soluble, or at least exhibit compatibility, with the solvent used in the composition. Many dispersants may be used, including but not limited to cationic surfactants, anionic surfactants, nonionic surfactants, amphoteric surfactants, modified polyacrylate polymers, ester of organic/inorganic acids, salts of organic/inorganic acids, polyester derivatives, polyamide derivatives, polyether derivatives, glycol derivatives, inorganic or organic acids, and mixtures thereof. Dispersant components may be present in amount ranges from 0.01-10% by weight and 0.1-5% by weight, wherein 0.1-5% by weight is preferred.

[0046] Defoamer components

[0047] A defoamer may be used to reduce or eliminate the air bubbles formed during the mixing process to create the compound. Defoamers may be oil based, solvent based, silicone based, modified polysiloxane based and/or silica based. An example of defoamer that may be used is Syco 711 or Syco 730 by Tygo Quimica Ltda, BU Syco Solutions Brazil, Sao Paulo, Brazil. Defoamer components may be present in amount ranges from 0.01-5% by weight and 0.1-2% by weight, wherein 0.1-2% by weight is preferred.

[0048] Alkalizing component

[0049] The alkalizing component may be any additive capable of raising the pH of the composition to alkaline levels. Alkalizing agents may include organic and/or inorganic bases. These may include, but are not limited to, amine, carbonate, ammonia, hydroxide, amide or silicate derivatives, etc. A specific example of alkalizing agent that may be used is an ammonium hydroxide in 25% aqueous solution by Amonex of Sao Paulo, Brazil. Alkalizing components may be present in amount ranges from 0.01-10% by weight, 0.05-5% by weight, and 0.1-2% by weight, wherein 0.1-2% by weight is preferred.

[0050] Preservative component

[0051] The preservative agent may be added to prevent, or at least inhibit, contamination of the hydrated silica composition during storage of the compound, after the compound is applied, or both. The preserving agent may achieve this by inhibiting the growth of, or even killing, bacteria, fungi, and/or algae. Preservatives that may be used include but are not limited to thiazolinone derivatives (BIT, MIT, CMIT, OIT etc.), imidazole derivatives (TMAD, etc.), bronopol, butylcarbamate derivatives (IPBC, etc.), phenolate derivatives (PCMCNa, etc.), salts of biphenylol (OPPNa, etc.), biphenylol (OPP), dimethanol derivatives (EDDM, etc.), hydantoin derivatives (DMDMH, etc.), propionamide derivatives (DBNPA, etc.), pyridine derivatives (NaPt, etc), oxazolidine derivatives (MBO, etc.), salts of zinc, silver or copper, terbutryne, and mixtures thereof. Preservative components may be present in amount ranges from 0.01-5% by weight and 0.1-1.5% by weight, wherein 0.1-1.5% by weight is preferred.

[0052] Anti-corrosion component

[0053] Anti-corrosive agents may be used to protect the in-can corrosion attacks from the water on the metal or alloy used on the inner side of packing gallons, avoiding loss of the compound's characteristics or stability. Anti-corrosive components may be present in amount ranges from 0.01-5% by weight and 0.01-0.2% by weight, wherein 0.01-0.2% by weight is preferred. Anti-corrosive agents that may be used include but are not limited to phosponate salts, phosphate salts, phenol derivatives, sulfur compounds, modified carboxylic acids, amine derivatives, hydrazine derivatives, organic acid derivatives, salts of organic acids, triazole derivatives, tannin derivatives, rosin derivatives, and copper, nitrite, zirconium, or zinc salts.

[0054] Coalescing component

[0055] Coalescing agents are used for optimizing the film formation process of the binder particles. The film formation process in compounds involves the coalescence of the polymeric particles, during and after the evaporation of the diluents (notably water), thereby permitting contact and fusion of adjacent polymeric dispersion particles. Coalescing agents typically reduce the minimal formation temperature and as a consequence to optimize film coherence and properties such as scrub resistance, mechanical properties as well as appearance. Coalescing components may be present in amount ranges from 1-20% by weight and 4-15% by weight, wherein 4-15% by weight is preferred, based on the resin binder content of solids. Useful coalescing agents include, for example, but are not limited to ester derivatives, glycol derivatives, fatty acid derivatives, isobutyrate derivatives, propionates derivatives, carboxilic acid derivatives, methacrylate derivatives, acetoacetates derivatives, and mixtures thereof.

[0056] With or without the additional additives, the hydrated silica composition may exhibit a multitude of beneficial properties. These may include, but are not limited to, thermal insulative properties, light reflective properties, lower mass density, quicker drying time, resistance to corrosion (salt, weather, alkalinity, etc.), acoustic properties, and other properties such as strength, hardness, opacity, color, etc.

[0057] Thermal insulative properties

[0058] The hydrated silica composition may be configured to provide thermal insulation by reducing thermal transfer rates through the compound. Thermal insulation properties of the spackling compound may depend on the composition (the type of components and relative amounts), color, and/or the thickness of the spackling compound. Generally, the compound becomes more thermally insulative with increasing amounts of hydrated silica (preferably, hydrogel silica type), increased lightness in color, and increased thickness of the compound's application onto a surface.

[0059] Hydrated silica has a high specific heat. When used in the hydrated silica

composition, it acts to slow the rate of heat transfer through the compound, thereby increasing thermal insulation effects of the compound. Compared at the same pressure and at 25°C

(measured at Decagon Devices Latam Ltda, Sao Paulo, by using a KD2-Pro instrument with SH- -3 -1

1 sensor for powders), the specific heat of hydrated silica (Britesorb® A 100) was 1.6 MJ-m -K

-3 -1

, as compared to 1.1 MJ-m^" K^~ for dolomites. The following test results confirm the increased thermal insulative effects described above.

[0060] Example I

[0061] A 4 mm thick layer of Composition I compound (See Table I) and a 4 mm thick layer of conventional heavy-duty putty (MassaCorrida CORAL® from AkzoNobel) were applied adjacent to each other on a galvanized steel plate (1mm thick) and left to rest during one day. The plate was then subjected to a heating process in which it was placed in an oven at approximately 50 °C for 30 minutes. A 20-person sensory evaluation panel was used to conduct a blind touch-feel test. Participants were asked to identify which surface felt warmer by touching the coated regions without touching the heated plate. 100% of the participants identified the Composition I spackling compound as the lower thermal transfer compound.

[0062] Example II

[0063] A second test was conducted in which two different galvanized steel plates (each 1 mm thick) were used. A 2 mm thick layer of Composition II (See Table II) was applied to the first plate, and the second plate was left bare without any coating. Within an ambient temperature environment of 25 °C, a first surface of each plate was exposed to a same heat source of a dichroic lamp of 50 watts, simulating the sunlight, at a distance of 10 cm from the plate surfaces for 1 hour to achieve a temperature of approximately 165 °C at the first surface of each plate. This was performed at 70% RU, or relative humidity in the room. To measure thermal transfer differences, a thermocouple was positioned next to each plate's second surface (a surface opposite that of the first surface) without making physical contact to the plate. The temperature readings from the thermocouple positioned next to the Composition Il-covered plate and the bare plate were 28 °C and 37 °C, respectively.

[0064] Fumed silica and/or aerogel silica may exhibit better thermal insulative properties, when compared to precipitated silica, as reported in U.S. Pat. No. 8,603,353; however, precipitated and hydrogel silica are lower in cost than their fumed or aerogel counterparts and may be a cost-efficient alternative. Uses of fumed silica and aerogel silica as thermal insulation materials are reported in U.S. Pat. Nos. 5,122,291, 4,636,415, EP 355295, EP 396961 or in EP 463311. While fumed silica and/or aerogel silica may be included within a composition of the present invention, use of at least one of precipitated silica and hydrogel silica is preferred.

Inclusion of fumed silica and/or aerogel silica in a composition may produce deleterious effects, such as a significant increase cost for example. The increase in cost may be especially apparent when including fumed silica and/or aerogel silica for purposes of achieving a desired thermally insulative property of the composition. In contrast, precipitated silica and hydrogel silica may be used to generate the same, if not better, thermally insulative property at a significantly reduced cost. Embodiments of the invention may specifically exclude fumed silica and/or aerogel silica.

[0065] Lighter color spackling compounds may absorb less light, as well as exhibit higher light reflectance. Thus, pigments may be added to the hydrated silica composition to further enhance insulative properties of the compound. This may be achieved, for example, by including titanium dioxide (white pigment) with the spackling compound.

[0066] Such thermal insulative hydrated silica compositions may be well suited for "thermal comfort" pastes/coatings, which are generally recommended, approved, and/or required for "green" building construction and energy saving projects. Prior art compounds that surport providing thermal comfort compounds include Telhado Branco® fom Hydronorth Tintas e Resinas, Parana, Brazil, Nanothermic 1® from Nanotech do Brasil, Sao Paulo, Brazil, and Tinta Emborrachada from Anjo Tintas, Santa Catarina, Brazil. These compounds include nanometer spheres having hollow ceramic/glass, resins in addition to additives mixed into the compound to reflect solar radiation, which typically require applying the compound via airless techniques. These are not required with our hydrated silica. Furthermore, microspheres are relatively more expensive than hydrated silica. Airless spray, or airless technique, is a method of atomizing paint/compounds with low viscosity without the use of compressed air. The paint is pumped under high pressure through a supply line to an airless gun. The paint is forced at high pressure through a small opening at the front of the valve, called the orifice, or spray tip. The tip restriction (orifice) forms a spray pattern that easily and fast cover the surface to be protected. The break-up of material into small droplets is called atomization. When airless spray is used to apply the compound, lower viscosity will almost always produce a finer atomization.

[0067] Exemplary compositions of hydrated silica compositionsare listed in Tables I and II:

Water 42.67 426.7

Anti-Corrosive (Sodium Nitrite) 0.03 0.3

Alkalizing Agent (Amonex ) 0.30 3.0

Defoamer (Syco 711) 0.20 2.0

Dispersant (Polysal ^' BA) 0.15 1-5

Preservative (Bodoxin^® AX) 0.15 1.5

Resin Binder (RA 193) 7.00 70.0

Table I Lightweight spackling compound - Composition I

Components Weight % Weight (Kg)

Water 31.10 311.0

Anti-Corrosive (Sodium Nitrite) 0.10 1.0

Alkalizing Agent (Syco 099) 0.60 6.0

Wetting Agent (Ultranex NP 95) 0.10 1.0

Preservative (Acticide HF) 0.25 2.5

Preservative (Acticide^® LPB 24) 0.30 3.0

Kesin tsinuer ^KA iyo; o a. nunu Q OnU. ΠU

Coalescing agent (Syco 100) 1.00 10.0

Hvdrated Silica (Britesorb^® A 100) 45.0 450.0

Table II Thermal coating compound - Composition II [0068] The compounds depicted in Tables I and II are exemplary and are not to be viewed as limiting the scope of the various possible compositions that may be formulated to generate a hydrated silica composition. It should be noted that Tables I and II both show results of standard testing procedures commonly used in Brazil, as well as identify the NBR code for interior applications over sealed concrete walls.

[0069] As described above, the hydrated compound may exist in a powder form, a liquid form, a paste form, and/or putty form. For example, Composition I may be presented in paste form for application by spreading onto a surface with a knife or trowel, while Composition II may be presented in liquid form for application by brushing, rolling, or spraying. In powder form, solvent (e.g., water) may be added to generate a liquid, paste, and/or putty having a desired consistency and/or viscosity before applying the compound. Similarly, the

thickness/viscosity/consistency of any form of compound (powder or otherwise) may be tailored by mixing desired amounts of solvent within the compound. This may be done to generate a compound that easily spreadable by trowel, or easily sprayed from a sprayer, etc.

[0070] Method of Manufacture

[0071] The method describe below pertains to an exemplary method for manufacturing Composition I; however, the method of manufacture may be applicable to other compositions as well. A mixer machine having stainless steel cowls impellers with a toothed disk shape may be used to agitate at 200 rpm a vat of a mixture of hydrated silica and solvent in a stainless steel vessel capable of containing 1000 Kg of hydrated silica composition, which includes 426.7 Kg of water and 0.3 Kg of sodium nitrite. On this first step, the mixer was used to moderately stir- agitate the hydrated silica composition and any additional salt additives to ensure complete solubilization of components as they are added. During stir-agitation, the following components may be slowly added until completely incorporation: 50.0 Kg DIBP; 3.0 Kg ammonium hydroxide 25% solution; 2.0 Kg Syco 711 ; 1.5 Kg Polysal® BA; 1.5 Kg Bodoxin® AX; and, 6.0 Kg turpentine. The mixture is then allowed to sit for 15 minutes.

[0072] On this second step, the liquid additives were added until complete solubilization. It is important that the liquid and salt addtives were completely solubilized in water before starting the dispersion of Silica, thus preventing the additive becomes encapsulated within the silica pores or non- solubilized. 400.0 Kg of Britesorb® A 100 is then added and the stirring may then be reconvened at 700 rpm or an rpm for which the impellers form a vortex. Stir- agitation may be continued at this rpm for 30 minutes. A vortex is needed to be formed in order to ensure a sufficient shear force to disperse the silica, deagglomerating its particles and increasing the dispersion stability. After dispersing the silica, the stir rate is reduce before adding the resing binder, thickener and paraffin, ensure that the shear force will not compromise the performance of polymers and emulsions. Then, the stir rate is reduced to 200 rpm and 70.0 Kg of RA193, 15.0 Kg of Latekoll® BA 800, and 24.0 Kg of Arpel PA450 may be added while stirring is continued. The mixture may be stir- agitated for another 15 minutes. The resultant mixture may be allowed to rest for at least five days before being subjected to quality inspection and packaging. The rest is needed to increase the compatibility of the dispersion of silica and additives in water, avoiding cracking on the dried film or drop on performance.

[0073] Methods of applying hydrated silica composition

[0074] Hydrated silica composition may be applied by using spray techniques, airless, transfer roller painting, hand painting, and/or spreading with a knife or trowel. For example, the hydrated silica composition may be applied manually (e.g., roller painting, hand painting, and/or spreading with a knife or trowel) and/or by machine (e.g., spray techniques and airless).

Therefore, the method of applicability may dictate the consistency, density, and viscosity of the hydrated silica composition.

[0075] As an example, hydrated silica composition in the form of putty may be used to cover small holes and cracks of interior and exterior surfaces. As another example, the hydrated silica composition putty may be used for decorative or artistic purposes to not only cover a structure, but to also generate an aesthetic or artistic appeal. As another example, hydrated silica composition may be used to cover a structure to provide thermal insulation. Further examples may include using the hydrated silica composition to cover defects, such as nail or screw holes in drywall, depressions and holes in wallboard, and/or general imperfections of a facade or wall. Correcting an imperfection may include leveling shallow surface defects of a wall or ceiling. Other uses may include preparing a structure to receive a topcoat of paint, thereby acting as an undercoat or primer.

[0076] In using the hydrated compound as an undercoat or primer before a topcoat of paint is applied to a structure, the following method steps may be used. It should be noted that the following method is exemplary, and that other methods of applying the hydrated silica composition may be used. Applying the hydrated silica composition may be done while the ambient temperature is above 10 °C and relative air humidity is below 90 percent. The structure to be coated should be properly cleaned and dry before any container housing the hydrated silica composition is opened.

[0077] If the structure is concrete, the concrete should be cured, dried, cleaned, and free of large imperfections, molds, holes, cracks, and residual loose particles before the compound is applied. If the concrete is not cured and/or is wet, users should wait until curing/drying is complete, which may take as long as 28 days. This may be necessary to allow the concrete structure to breath, as well as allow the room defined by the concrete structure to ventilate. All loose debris, cement, dust, and grease should be removed, which may be achieved with a brush.

[0078] If after a thorough cleaning, the concrete is still crumbling or it is still absorbent, a sealing or primer product may be used before applying the hydrated silica composition to assist with preventing further crumbling and to minimize any absorption effects of the concrete during the application the hydrated silica composition. Deep and large cracks and/or holes should be pre-filled with fresh concrete, plaster, and/or specific putties prior to applying the hydrated silica composition. Again, if any concrete is used, proper curing and ventilation times should be adhered to.

[0079] Open the package containing the hydrated silica composition and stir the compound thoroughly. Place a small amount of hydrated silica composition on a putty knife and wipe away any extra spackling with the edge of the putty knife. Run the putty knife flat against the structure and spread the hydrated silica composition in a vertical and/or horizontal direction, dragging the hydrated silica composition over the surface of the structure. Ensure to only apply a thin coating so as to correct minor defects of the structure. Allow the first coat to dry (e.g., approximately 2 hours). Use fine-grit sandpaper to sand the coated structure smooth after each coat is dried, followed by a wiping with a damp cloth to remove dust from sandpapering. This may be repeated two to three times, ensuring to allow the hydrated silica coating to dry thoroughly between each sanding session. After the final coat has dried and is completely smooth, the structure may then receive a coating of paint.

[0080] In using the hydrated silica composition to correct imperfections, the following method steps may be used. It should be noted that the following method is exemplary, and that other methods of applying the hydrated silica composition may be used. The hydrated silica composition may be used to patch small holes, cracks, and other imperfections. These imperfections may be no larger than 5 millimeters, and preferably no larger than 2 millimeters. For repairing deep holes and cracks, concrete or spackling compounds exhibiting improved structural strength resistance, as reported in United States Patent No. 7,790,796 B2, are recommend.

[0081] Hydrated silica composition, when compared with common heavy-duty spackling pastes (based on calcium carbonate inorganic filler), exhibits a smaller shrinkage effect in small cavities. This effect is observed even with hydrated silica compositions formulated with lower content of solids than that of the heavy-duty spackling pastes. Known heavy-duty spackling paste (with calcium carbonate as the main filler) exhibits an average dry content of solids of at least 60% by weight and shrink approximately 25% by volume. In contrast, a hydrated silica composition with Britesorb® A 100 as the filler and 25% by weight of dry content of solids shrinks 5% by volume.

[0082] Before applying the hydrated silica composition, clean and smooth the area around the defect. This may be done to maximize adhesion of the compound to the structure. Often, a defect in drywall, for example, is caused by blunt force or by a screw, nail or other type of fastener. Such defects may have an outer edge or a plurality of fragments that protrude outward. Gently scrape away the loose paint and protruding fragments with a putty knife or similar tool until the surface around the hole is as smooth as the rest of the drywall.

[0083] Two putty knives, one with a wide blade and one with a narrow blade, may be used to apply the compound to the defect. The wider knife may be dipped in a container of hydrated silica composition and used as a palette. The narrow knife may be used to apply the compound by scraping compound from the wider knife and pressing the narrower knife firmly against a wall at an angle to smear a volume of compound into the defect. This is continued until the defect is filled and the area over the defect is flush with the rest of the wall due to the fill of the compound. Using two knives may allow for a cleaner, more controlled application. Excess putty may be scraped from the wall, with care taken to avoid disturbing any recently-repaired areas. After fully dried (e.g., a few hours), the corrected area may be sanded to obtain a uniform surface and to prepare the surface for painting or additional application of the compound. If the compound depresses slightly below the surface of the wall so as to no longer be flush, one may reapply a small amount of compound. After the recently-repaired areas have completely dried, a damp cloth may be used to remove excess compound.

[0084] In using the hydrated silica composition to generate a decorative and/or artistic appeal, the following method steps may be used. It should be noted that the following method is exemplary, and that other methods of applying the hydrated silica composition may be used. Various pigments and various hydrated silica particle sizes may be used to modify color, opaqueness, reflectance, smoothness, etc. Embodiments with pigment may be used with the purpose of decorative or artistic effects on interior/exterior surfaces, as well as on any portion of the interior and/or exterior structure. Applications of the compound may be the finished coating or additional top coatings of decorative paint, primer, and/or varnish may be used. Decorative and artistic applications may use the same methods of applying the compound as described above.

[0085] The properties exhibited by the hydrated silica composition enable the use of the compound with additional benefits as compared to prior art compounds. Some of these additional benefits are lower packaging and shipping costs. As described above, heavy-duty spackling exhibits an average specific gravity of 1.7 g/cm , while the spackling paste composition from at least one embodiment of the present invention provides an average specific gravity of 0.1-2.5 g/cm³, 0.2-2.5 g/cm³, 0.3-2.5 g/cm³, 0.4-2.5 g/cm³, 0.5-2.5 g/cm³, 0.6-2.5 g/cm³, 0.7-2.5 g/cm³, 0.8-2.5 g/cm³, 0.9-2.5 g/cm³, 1.0-2.5 g/cm³, 1.1-2.5 g/cm³, 1.2-2.5 g/cm³, 1.3-2.5 g/cm³, 1.4-2.5 g/cm³, 1.5-2.5 g/cm³, 1.6-2.5 g/cm³, 1.7-2.5 g/cm³, 1.8-2.5 g/cm³, 1.9-2.5 g/cm³, 2.0-2.5 g/cm³, 2.1-2.5 g/cm³, 2.2-2.5 g/cm³, 2.3-2.5 g/cm³, or 2.4-2.5 g/cm³. As a result of this considerable mass density reduction, a reduction in the average weight of 18 liter packages drops from 30 Kg to 20 Kg. End users who may have to carry multiple packages to complete a spackling job, for example, would realize considerable improvements with workplace safety in relation to the handling such packages. In addition, this considerable weight reduction of the same packaging volume increases the number of packages that may be transported on the same freight by 50%. Furthermore, this considerable weight reduction enables manufactures and suppliers to use lighter and more cost-effective packaging for the compound.

[0086] The lower mass density also improves ergonomics of applying the compound. The lighter weight enables easier wielding of a putty knife and quicker transfer of the compound from the putty knife to the structure. As a result, a user does not need to exert as much effort to position the putty knife, which enables more precise and accurate movement with ease and efficiency. In addition, shorter drying times of the hydrated silica composition may also increase worker productivity.

[0087] Hydrated silica compositions provide better sanding properties (in terms of producing less dust) due to the lower shear force required to sand the compound. This not only increases workplace safety and worker productivity, but it also increases compound yield per applied area. Less dust also requires less after-cleaning, which further increases worker productivity. For example, Composition I, as reported below, was sanded in accordance to the NBR15312 of Abrasion Resistance resulting in 3.3g of dust; on the other hand, a Suvinil Massa Corrida® from BASF (heavy duty spackling paste) achieved 5.0 grams of dust, showing that Hydrated silica compositions generate less dust and low abrasion resistance. The yield achieved with

composition I per applied area was 30-40% higher than the heavy duty spackling paste.

[0088] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings of the disclosure. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternate embodiments may include some or all of the features disclosed herein. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention, which is to be given the full breadth thereof. Additionally, the disclosure of a range of values is a disclosure of every numerical value within that range, including the end points.

Claims

WE CLAIM:

1. A hydrated silica composition, comprising:

1- 95% by weight of hydrated silica component with a particle size distribution ("PSD") D50 within a range from 0.1-100 microns;

0.01-90% by weight of water; and,

at least one of an ancillary low-density filler agent, a resin binder agent, a pigment agent, a thickener agent, an emulsion agent, a plasticizer agent, a dispersant agent, a defoamer agent, an alkalizing agent, a preservative agent, an anti-corrosive agent, and a coalescing agent.

2. The hydrated silica composition recited in claim 1, wherein the hydrated silica is selected from the group consisting of precipitated silica and hydrogel silica.

3. The hydrated silica composition recited in claim 1, wherein the hydrated silica is present in an amount from 30-50% by weight of the composition.

4. The hydrated silica composition recited in claim 1, wherein the hydrated silica component is present within a PSD D50 range from 5-30 microns.

5. The hydrated silica composition recited in claim 1, wherein the hydrated silica component is present within a PSD that includes a D50 greater than 100 microns.

6. The hydrated silica composition recited in claim 1, wherein the hydrated silica component has a silica to water mass ratio of 0.1-99.9% silica:0.1-99.9% water.

7. The hydrated silica composition recited in claim 1, wherein the hydrated silica composition has a specific gravity within the range from O. lg/cm 3 to 2.5 g/cm 3.

8. The hydrated silica composition recited in claim 1, wherein the hydrated silica component has a specific heat greater than 1.1 MJ-m -^"3 K -^~1.

9. The hydrated silica composition recited in claim 1, wherein the hydrated silica composition is effective as a member of the group consisting of an undercoat on an ancillary structure before a topcoat of paint is applied; as a composition to correct surface imperfections within an ancillary structure, wherein the imperfections are smaller than 5 millimeters; to provide at least one of a decorative and artistic appeal; as a thermal insulator; and, as a composition to cover interior or exterior ancillary walls, ceilings, floors, or roofs, wherein the interior or exterior walls, ceilings, floors, or roofs comprise at least one of concrete gypsum, drywall, plaster, wood, fibrocement, ceramics, plastic, and metal.

10. The hydrated silica composition recited in claim 1, wherein the hydrated silica composition is in powder form, wherein mixing the powdered hydrated silica composition with water generates a liquid or paste.

11. A method for applying spackle to a structure, comprising applying to a structure in need of spackle, a spackling comprising the hydrated silica composition of claim 1.

12. A method for changing the mass density and thermal insulative properties of the hydrated silica composition of claim 1, comprising adding at least one ancillary low-density filler agent.

13. The hydrated silica composition of claim 1, wherein the composition is between 15 and 50% solids by weight.

14. The hydrated silica composition recited in claim 1, wherein the hydrated silica composition is water-based, and wherein the water is 60-80% by weight of the composition.

15. The hydrated silica composition recited in claim 1, wherein the hydrated silica composition has a low shear force required to sand, wherein sanding according to NBR15312 of abrasion resistance results in about 3.3g of dust.

16. A hydrated silica composition, comprising:

1- 95% by weight of hydrated silica component with a PSD D50 within a range from 0.1- 100 microns;

20-60% by weight of water;

5-10% by weight of ancillary low-density filler;

0-7% by weight of resin binder; -10% by weight by weight of a pigment;

0-7% by weight of plasticizer;

0-5% by weight of water repellant emulsion;

0-5% by weight of thickener;

0-1.5% by weight of preservative;

0-2% by weight defoamer;

0-5% by weight dispersant;

0-5% by weight solvent other than water;

0-15% by weight coalescing agent;

0-2% by weight alkalizing agent; and,

0- 0.2% by weight anti-corrosion agent.

17. The hydrated silica composition of claim 16, compr

2- 7% by weight of resin binder;

0.05- 10% by weight by weight of a pigment;

3- 7% by weight of plasticizer;

1- 5% by weight of water repellant emulsion;

0.3-5% by weight of thickener;

0.1-1.5% by weight of preservative;

0.1-2% by weight defoamer;

0.2-1% by weight dispersant;

0.1-5% by weight solvent other than water;

4- 15% by weight coalescing agent;

0.1-2% by weight alkalizing agent; and, 0.01-0.2% by weight anti-corrosion agent.