WO2014049189A1 - Composition and method for producing reinforced ceramic tiles made from porcelain stoneware - Google Patents

Composition and method for producing reinforced ceramic tiles made from porcelain stoneware Download PDF

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Publication number
WO2014049189A1
WO2014049189A1 PCT/ES2013/070667 ES2013070667W WO2014049189A1 WO 2014049189 A1 WO2014049189 A1 WO 2014049189A1 ES 2013070667 W ES2013070667 W ES 2013070667W WO 2014049189 A1 WO2014049189 A1 WO 2014049189A1
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Prior art keywords
weight
porcelain stoneware
proportion
obtaining according
expressed
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PCT/ES2013/070667
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Spanish (es)
French (fr)
Inventor
José Francisco FERNÁNDEZ LOZANO
Julián JIMÉNEZ REINOSA
Enrique VELA CARRASCOSA
Fernando GARCÍA TOMAS
Original Assignee
Consejo Superior De Investigaciones Científicas
Vicar, S. A.
Pasek Minerales, S. A. U.
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Publication of WO2014049189A1 publication Critical patent/WO2014049189A1/en

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    • C04B33/00—Clay-wares
    • C04B33/02—Preparing or treating the raw materials individually or as batches
    • C04B33/04—Clay; Kaolin
    • C—CHEMISTRY; METALLURGY
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    • C04B33/00—Clay-wares
    • C04B33/02—Preparing or treating the raw materials individually or as batches
    • C04B33/13—Compounding ingredients
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
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    • C04B33/00—Clay-wares
    • C04B33/24—Manufacture of porcelain or white ware
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    • C04B33/34—Burning methods combined with glazing
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    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
    • C04B41/81—Coating or impregnation
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    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
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    • C04B2235/3418—Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
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    • C04B2235/3427—Silicates other than clay, e.g. water glass
    • C04B2235/3436—Alkaline earth metal silicates, e.g. barium silicate
    • C04B2235/3445—Magnesium silicates, e.g. forsterite
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    • C04B2235/3472—Alkali metal alumino-silicates other than clay, e.g. spodumene, alkali feldspars such as albite or orthoclase, micas such as muscovite, zeolites such as natrolite
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Definitions

  • the present invention belongs to the field of the preparation of formulations for the ceramic industry, in particular in applications of formulations for the production of porcelain stoneware both for the production of ceramic tiles and for ceramic products in their application in structural ceramics and ornamental ceramics. More specifically, the present invention relates to a new type of compositions and the process for obtaining ceramic porcelain stoneware products with a marked improvement in their mechanical strength.
  • Porcelain stoneware is a ceramic product that is vitrified throughout its mass and is very compact, which has as its essential characteristic a low and closed porosity. This material has excellent mechanical and chemical properties, which allow its use, for example, as flooring or cladding both indoors and outdoors. In addition, it has a high modulus of breakage (high mechanical strength) and toughness, with mechanical flexural strengths typically between 250 and 500 kg / cm 2 .
  • a porcelain-type vitrified product is characterized by having a microstructure that combines a vitreous matrix in which different crystalline phases are located.
  • the most common crystalline phases found in sintered stoneware are quartz, mullite, alumina, zircon, anortite and ganhite. While certain crystalline phases come from the starting products, others are consequences of chemical reactions that take place at high temperature during heat treatment.
  • Porcelain stoneware requires a well-known ceramic process that corresponds to a technologically mature process that consists, in broad strokes, of obtaining a homogeneous mixture of raw materials, forming the part and performing a heat treatment at temperatures above 1 100 ° C.
  • nanocrystalline mullite is formed, the proportion of alumina contributed by the raw materials used in the manufacture of porcelain stoneware, such as kaolinitic clays, quartz and feldspars, does not exceed 15% by weight and therefore the proportion of mullite is very limited .
  • the solution consisting of the incorporation of synthetic products such as AI2O3 is economically unfeasible.
  • quartz polymorphism of S1O2.
  • the presence of quartz in porcelain stoneware occurs as a result of the incorporation of said phase in the form of siliceous sands.
  • the quartz crystals also provide excellent wear resistance properties.
  • the percentage of quartz in a porcelain composition is limited by generating problems of efficient forming of parts, particularly if they are large formats.
  • the iron and magnesium minerals used are very abundant minerals in nature.
  • a first aspect of the present invention relates to a porcelain stoneware comprising silicate crystals selected from the list comprising magnesium silicates, iron silicates and magnesium and iron silicates, preferably iron and magnesium silicates, where the crystals are homogeneously distributed and have an average size of 20 nm to 1000 nm, preferably 50 to 500 nm and more preferably 80 to 200 nm.
  • a second aspect of the present invention relates to the process for obtaining porcelain stoneware as described above, comprising the steps of: a) mixing in aqueous medium of: i) at least one plastic clay in a proportion of 40% to 70% in weight,
  • a third aspect of the present invention relates to the use of porcelain stoneware as described above as a cover or decorative piece for floors, walls, facades, furniture or sanitary ware.
  • pillain stoneware is meant a hard ceramic material, vitrified in all its mass and very compact, which presents as an essential characteristic a low and closed porosity, mechanical properties such as resistance to breakage and wear resistance, resistant to chemical attack and practically waterproof. To obtain it, it is based on a composition based on natural raw materials such as clay, quartz and feldspar.
  • silicate crystals means a homogeneous solid that has an ordered internal structure of its reticular particles, the chemical composition of which comprises SiO x groups.
  • a "plastic clay” is a clay that forms a moldable mass when mixed with water.
  • clay is meant hydrated aluminum silicates, from the decomposition of aluminum ores.
  • plastic clays kaolinite, smectite and illite clays are considered.
  • iron ore, magnesium or iron and magnesium means a solid chemical substance formed by biogeochemical processes that has a characteristic chemical composition (but variable within limits and an orderly atomic structure comprising cations of iron, magnesium or iron and magnesium respectively.
  • a “sand” or “quartzite sand” is an unconsolidated sedimentary material present in nature with a particle size between 0.2 ⁇ and 5000 ⁇ comprised mostly of crystalline particles of S1O2, generally in its polymorphic variety of quartz.
  • feldspar means a group of minerals comprising aluminum and calcium silicates such as anortite, of general formula CaAl2S ⁇ 20s, or sodium silicates such as albite of general formula NaAISi 3 0 8 , or potassium silicates such as potassium feldspar of general formula KAIS1O3O8, or mixtures of these bases.
  • baking is meant to undergo a heat treatment comprising high temperatures, preferably temperatures above 500 ° C.
  • Coating or decorative piece means a piece used in construction that allows a surface to be coated, whether horizontal or vertical, interior or exterior, straight or curved.
  • a first aspect of the present invention relates to a porcelain tile that it comprises silicate crystals selected from the list comprising magnesium silicates, iron silicates or magnesium and iron silicates, preferably iron and magnesium silicates, where the crystals are homogeneously distributed and have an average size of 20nm to 1000nm, preferably 50nm at 500 nm and more preferably from 80 nm to 200 nm.
  • the silicate crystals belong to the olivine mineral group.
  • olivine mineral group also called peridot, is a magnesium and iron nesosilicate.
  • the olivine group comprises at its ends the minerals Fayalite (iron silicate) and forsterite (magnesium silicate) as well as the intermediate compositions (iron and magnesium silicates). These minerals crystallize in the orthorhombic crystalline group.
  • the silicate crystals obtained are also characterized by being abundantly and with a good dispersion in the vitreous matrix of the porcelain stoneware. These crystals produce a mechanical reinforcement of porcelain stoneware.
  • the distribution and dispersion of said crystalline phases allows a reinforcement of the vitreous matrix and contributes to the crack deflection mechanisms.
  • These phases are achieved using raw materials with an important content in iron and magnesium cations. In the porcelain stoneware products of the prior art, these cations are avoided because they generate high expansion coefficients, which hinder the correct coupling of the enamels on said pieces and prevent the enamelling of the pieces.
  • the porcelain stoneware further comprises quartz crystals, where the quartz crystals have an average size of 0.5 m to 100 ⁇ , preferably 1 ⁇ to 40 ⁇ and more preferably 2 ⁇ to 20 ⁇ . Quartz grains are characterized by rounded edges that indicate a partial dissolution in the vitreous phase and a good integration in it. These crystals act favorably from the mechanical point of view, as they reinforce the vitreous matrix by differences in coefficients of expansion.
  • the porcelain stoneware of the present invention comprises crystallizations corresponding to crystalline quartz phases and olivine crystalline phases.
  • the porcelain stoneware further comprises indialite crystals in a proportion less than 10%, preferably less than 5% and more preferably less than 2%.
  • indialite is meant an aluminum and iron and magnesium cyclosilicate, which is a high temperature polymorph of cordierite. Cyclosilicates are silicates that have bound tetrahedra, with a Si: 0 1: 3 ratio. Its formation in a porcelain produces crystals of microcrystalline size, reduces the mechanical properties of porcelain stoneware and significantly decreases the thermal coefficient of expansion.
  • the proportion of Mg expressed as a percentage by weight of the equivalent oxide with respect to the total weight, is 8% to 22%, preferably 10% to 20% and more preferably 12 % to 16%
  • the proportion of Fe expressed as a percentage by weight of the equivalent oxide with respect to the total weight, is from 2% to 15%, preferably from 3% to 10% and more preferably from 4 % to 6%
  • the porcelain stoneware further comprises Si proportions, expressed as a percentage by weight of the oxide equivalent to the total, is 40% to 70%, preferably 45% to 62% and more preferably from 50% to 56%.
  • the porcelain stoneware also comprises proportions of Al, expressed as a percentage by weight of the oxide equivalent to the total, is 5% to 22%, preferably 8% to 20% and more preferably from 12% to 18%.
  • the porcelain stoneware further comprises Na, K and Ca in proportions of less than 5% expressed as a percentage by weight of the respective equivalent oxides with respect to the total weight.
  • the porcelain stoneware further comprises other minor compounds in a proportion less than 1% by weight with respect to the total composition.
  • the present invention allows to adapt the formulation for the development of porcelain stoneware compositions with different expansion coefficients and different sintering temperatures.
  • crystallizations that can be incorporated into porcelain stoneware are zircon crystals, corundum, spinels, garnets.
  • the effect of these other crystallizations is mainly related to the chromatic modification of the porcelain stoneware of the present invention.
  • the methods of chromatic modification of the porcelain stoneware by crystallized particles compatible with the vitreous phase of the porcelain stoneware are well described in the state of the art.
  • the Porcelain stoneware density is at least 2.4 g / cm 3 , preferably at least 2.5 g / cm 3 .
  • sintered materials have closed porosity and a water adsorption coefficient of less than 0.5%.
  • the coefficient of thermal expansion in the range 50-300 ° C is less than 70x10 "7o C " 1 , preferably less than 60x10 "7o C " 1 .
  • the expansion coefficient is maintained at adequate values due to the nature and size of the phases formed.
  • the porcelain stoneware products of the present invention have a good mechanical strength, with modules of mechanical flexural strength of at least 800 kg / cm 2 and preferably of at least 1000 kg / cm 2 .
  • the mechanical impact resistance determined by means of the restitution coefficient by means of ISO 10545-5: 1996 in the porcelain stoneware samples of the present invention reaches values of 0.80 and preferably 0.85 which are advantageous against the coefficients. of restitution for porcelain stoneware materials in the state of the art, which are less than 0.70. A higher coefficient of restitution implies greater impact resistance.
  • the porcelain stoneware further comprises a slip layer.
  • a slip layer is meant a layer that covers the exposed face of the piece of porcelain stoneware, preferably composed of light clays, and whose purpose is to make the surface of the porcelain stoneware opaque and whiten, thus solving the limitations that may arise from the surface coloring of the porcelain stoneware of the present invention.
  • the porcelain stoneware further comprises an enamel layer.
  • "Enamel” means a vitreous material that is applied to decorate and color the piece of porcelain stoneware. Enamel is the result of the melting of powdered glass through a heating process. In the enamelling process the support is covered by a layer of enamel that can be decorated with ceramic pigments. This layer of Enamel can be applied on porcelain stoneware surfaces previously coated or not by a layer of engobe. This eliminates the limitations that could be derived from the color of the pieces for surface decoration processes.
  • a second aspect of the present invention relates to the process for obtaining porcelain stoneware as described above, comprising the steps of: a) mixing in aqueous medium of: i) at least one plastic clay in a proportion of 40% at 70% by weight,
  • the plastic clay comprises phyllosilicates.
  • clays for white pastes are clay minerals associated with the types of ball clay or China clay, of an illicit-kaolinitic or kaolinitic nature.
  • Clays for white pasta are characterized by the contribution of alumina of the composition and for having a low content in iron cations.
  • Clays for red pasta are clay minerals of an illicit-chlorite or illitic-kaolinite nature. Clays for red pasta have important contents of iron cations that give them the characteristic reddish color.
  • Philosilicates are preferably of an illitic-kaolinitic or kaolinitic nature. Or illitic-chlorite.
  • the quartzitic sand or sand comprises crystalline quartz particles.
  • Quartz is a mineral composed of silicon dioxide known as silica, Si0 2 , widely described and known in the state of the art and having a high hardness.
  • the feldspar comprises a group of tectosilicate minerals that are constituted primarily of igneous type rocks.
  • the iron ore, magnesium or both is a nesosilicate, preferably of the olivine group.
  • Said iron and magnesium minerals are preferably of magmatic origin. These minerals are part of dunites and peridotites, or are associated with pyroxene and chromite-like phases. They are also the main mineral component in gabros, basalts and kimberlites. It can also be in combination with silicates such as chlorites, talcs and brucites.
  • the proportion of Mg, expressed as a percentage by weight of the equivalent oxide with respect to the total weight is 8% to 22%, preferably 10% to 20% and more preferably 12% at 16%
  • the proportion of Fe expressed as a percentage by weight of the equivalent oxide with respect to the total weight it is from 2% to 15%, preferably from 3% to 10% and more preferably from 4% to 6%
  • the proportion of Si expressed as a percentage by weight of the equivalent oxide with respect to the total, is 40% to 70%, preferably 45% to 62% and more preferably 50 % to 56%.
  • the proportion of Al expressed as a percentage by weight of the equivalent oxide with respect to the total, is 5% to 22%, preferably 8% to 20% and more preferably 12 % to 18%.
  • K and Ca expressed as a percentage by weight of the respective oxides equivalent to the total weight of less than 5%.
  • the method further comprises a step (a1) after (a) and before (b) adding at least one additive, wherein the additive is selected from the list comprising defloculates, dispersants, defoamers, bactericides, binders, plasticizers and waxes.
  • the additive is selected from the list comprising defloculates, dispersants, defoamers, bactericides, binders, plasticizers and waxes.
  • a "deflocculant” is a chemical that prevents the aggregation of solid particles in a colloidal dispersion, such as sodium silicate.
  • a "dispersant” is an additive that is used to make a solute have distribution and dispersion in a solvent, such as tripolyphosphate, tetrasodium pyrophosphate, ammonium polyacrylate and sodium polyacrylate.
  • An “antifoam” is a substance that reduces the surface tension of the suspension and prevents the appearance of foams during mixing, such as a siloxane polyester.
  • a "bactericide” is a substance that prevents the proliferation of bacteria in the preparation of porcelain stoneware. Examples of suitable bactericidal substances are quaternary amines.
  • a "binder” is a chemical that has the ability to agglomerate or bind fragments or particles, such as acrylic emulsions suspended in water, acrylic styrene latex, a polyvinyl alcohol or a methylcellulose polymer.
  • a “plasticizer” is a resin or polymeric substance that confers plasticity to the green ceramic mass, in particular under pressure deformation, such as polyethylene glycol.
  • a wax is a malleable organic chemical compound.
  • Synthetic waxes comprise high molecular weight alkanes, such as paraffins.
  • Natural waxes are fatty acid esters with high molecular weight alcohols, such as beeswax. Binders, plasticizers and waxes are especially used when the process comprises an extruded step.
  • the method further comprises a step (a2) prior to (b) homogenization by grinding or dispersion of the product obtained in the previous stage.
  • a2 prior to (b) homogenization by grinding or dispersion of the product obtained in the previous stage.
  • conventional systems of the ceramic industry can be used, such as grinding or dispersion.
  • the average particle size of the homogenization slip of the porcelain stoneware raw materials of the present composition will be such that the d90 (average equivalent diameter at 90% of the distribution) is less than 100 ⁇ .
  • drying is carried out by spraying.
  • the step of forming parts is carried out by uniaxial pressing, isostatic pressing, or extrusion of ceramic bodies in green.
  • the homogeneous mixture of raw materials is dried by atomizing processes to obtain a distribution of agglomerates suitable for forming parts by conventional processes such as uniaxial pressing or isostatic pressing.
  • a Adequate proportion of water that is above the solid limit of the referred formulation of the present invention can be formed by extruding ceramic bodies in green.
  • the method further comprises a step (c1) subsequent to (c) and prior to (d) engobe application.
  • the method further comprises a step (c2) prior to (d) enamelling of the product resulting from the previous stage.
  • This enamelling can be done on the piece of porcelain stoneware with or without engobe.
  • the enamelling process of the pieces with a layer of ceramic enamel gives the ceramic tile technical and aesthetic properties such as: impermeability, easy cleaning, gloss, surface texture, mechanical and chemical resistance, as well as extensive decoration possibilities.
  • the cooking of step (d) is carried out in an industrial cycle, preferably in monocoction in a fast-cooking single-layer gas oven.
  • the cooking temperature of step (d) is between 980 ° C and 1280 ° C, even more preferably between 1 100 ° C and 1200 ° C.
  • the proportions and temperature range are adjusted based on the alkali and alkaline earth earth cation content of the composition.
  • the modification of the composition of the porcelain stoneware of the present invention depending on the proportions of components used thus represents an advantage since it allows adjusting the temperature range in which densified materials are obtained.
  • This procedure is advantageous since it allows to obtain ceramic products in processes with different cooking temperatures.
  • An additional advantage of the procedure is that it allows adapting to the availability of different local raw materials, limiting dependence on Imported raw materials.
  • the cooking of step (d) comprises rapid sintering cycles with residence times at the maximum temperature of the cycles of between 1 and 30 minutes, preferably between 2 and 20 minutes and even more preferably between 3 and 10 minutes. Excellent results have been obtained when the residence time at the maximum temperature is 6 minutes.
  • sintering cycle is meant the thermal cycle that the formulation undergoes so that the necessary phases of the porcelain stoneware are formed.
  • the "residence time at maximum temperature” is the time that the formulation is subjected to the maximum temperature of the cycle. This maximum temperature is between 980 ° C and 1280 ° C, preferably between 1 100 ° C and 1200 ° C.
  • the total time of the thermal cooking cycle lasts between 30 and 100 minutes, preferably between 40 and 80 minutes and even more preferably between 45 and 60 minutes. Cooking is preferably carried out under oxidizing atmosphere.
  • a third aspect of the present invention relates to the use of porcelain stoneware as described above as a covering or decorative piece in floors, walls, facades, furniture, sanitary ware. Due to the high mechanical strength of the porcelain stoneware products of the invention, in a preferred embodiment of the third aspect of the present invention, the part is large format.
  • the term "large format" in the context of the invention means formats with surfaces greater than 0.20 m 2 , preferably formats greater than 0.30 m 2 .
  • FIG. one X-ray powder diffractogram of the sample of Example 1.
  • C Quartz
  • F Forsterite
  • E Soapstone
  • M Mullite
  • H Hercinite
  • I Intensity
  • A Angle 2 ⁇ (degrees).
  • FIG. 2 X-ray powder diffractogram of the sample of Example 3.
  • C Quartz, F: Forsterite, E: Soapstone, M: Mullite, H: Hercinite; I: Intensity; A: Angle 2 ⁇ (degrees)
  • FIG. 3 Scanning Electron Microscopy (SEM) micrograph of the polished surface and chemically attacked with hydrofluoric acid corresponding to the sample of Example 1.
  • FIG. 4 SEM micrograph of the polished and chemically attacked surface corresponding to the sample of example 1. Detail of the submicron crystalline phases.
  • Example 1 Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
  • dunite magnesium iron silicate
  • quartz quartz
  • composition expressed as a percentage in oxide equivalent to the total is:
  • the above formulation was homogenized in aqueous medium at a concentration of 60% by weight solids content.
  • To this mixture was added 0.2% by weight of a sodium tripolyphosphate type dispersant and 0.05% by weight of an Additive type preservative.
  • the mixture was homogenized by milling in alumina ball mill to constitute a stable suspension. The grinding carried out allows a mixture of raw materials with a size such that the slippery residue when passing through a sieve of 63 ⁇ is less than 3% by weight.
  • This suspension was spray dried to obtain an agglomerate with a size distribution between 100-600 ⁇ .
  • the residual moisture of the atomized agglomerates was in a range of 4-7% by weight.
  • the agglomerates were formed in a tile by using a uniaxial press that used a pressing pressure of 250 kg / cm 2 .
  • the pressed green tiles were dried in an oven to remove the corresponding humidity.
  • the dried tile was heat treated at a temperature of 1 140 ° C in an oxidizing atmosphere in a fast-cooking monostrate oven in a 50-minute cycle. Maintenance time at maximum temperature was 6 minutes As a result, a porcelain stoneware support with the following physical properties was obtained:
  • Porcelain stoneware is also characterized by presenting the following crystalline phases identified by X-ray Diffraction (XRD) (Fig. 1):
  • These particles are characterized by having a grain size of less than 500 nm and being dispersed in the vitreous matrix to form the microstructure of the porcelain stoneware reinforced by the presence of submicron crystalline phases.
  • Example 2 Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
  • the same formulation as in example 1 and the same drying and forming was used.
  • the dry tile was heat treated at a temperature of 1,160 ° C in an oxidizing atmosphere in a fast-firing monolayer oven in a 50-minute cycle.
  • the maintenance time at maximum temperature was 6 minutes.
  • a porcelain stoneware support with the following physical properties was obtained:
  • Example 3 Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
  • dunite magnesium iron silicate
  • composition expressed as a percentage in oxide equivalent to the total is:
  • the porcelain stoneware material was processed following the procedure described in example 1 (maximum temperature 1 140 ° C). As a result, a porcelain stoneware support with the following physical properties was obtained:
  • Porcelain stoneware is also characterized by presenting the following crystalline phases identified by X-ray Diffraction (XRD) (Fig. 2):
  • Example 4 Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
  • composition expressed as a percentage in oxide equivalent to the total is:
  • the porcelain stoneware material was processed following the procedure described in example 1 (maximum temperature 1 140 ° C). As a result, a porcelain stoneware support with the following physical properties was obtained: density 2.42 g / cm "
  • Porcelain stoneware is also characterized by presenting the following crystalline phases identified by X-ray Diffraction (XRD):

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Abstract

The invention relates to porcelain stoneware comprising silicate crystals selected from a list comprising silicates of magnesium, silicates of iron or silicates of magnesium and iron, in which the crystals are evenly distributed and have an average size of between 20nm and 1000nm, preferably between 50 and 500nm. The invention also relates to the method for producing the porcelain stoneware products.

Description

COMPOSICIÓN Y PROCEDIMIENTO DE OBTENCIÓN DE AZULEJOS CERÁMICOS DE GRES PORCELÁNICO REFORZADOS  COMPOSITION AND PROCEDURE FOR OBTAINING CERAMIC TILES OF REINFORCED PORCELAIN TILES
D E S C R I P C I Ó N D E S C R I P C I Ó N
La presente invención pertenece al campo de la preparación de formulaciones para la industria cerámica, en particular en aplicaciones de formulaciones para la obtención de gres porcelánico tanto para la producción de baldosas cerámicas como en productos cerámicos en su aplicación en cerámica estructural y cerámica ornamental. Más concretamente, la presente invención se refiere a un nuevo tipo de composiciones y el procedimiento de obtención para obtener productos cerámicos de gres porcelánico con una notable mejora en su resistencia mecánica. The present invention belongs to the field of the preparation of formulations for the ceramic industry, in particular in applications of formulations for the production of porcelain stoneware both for the production of ceramic tiles and for ceramic products in their application in structural ceramics and ornamental ceramics. More specifically, the present invention relates to a new type of compositions and the process for obtaining ceramic porcelain stoneware products with a marked improvement in their mechanical strength.
ANTECEDENTES DE LA INVENCIÓN BACKGROUND OF THE INVENTION
Para la obtención del gres porcelánico se parte de una composición basada en materias primas naturales como son: caolín (o arcilla caolinítica), cuarzo y feldespato. El gres porcelánico es un producto cerámico que está vitrificado en toda su masa y es muy compacto, que presenta como característica esencial una porosidad baja y cerrada. Este material posee excelentes propiedades mecánicas y químicas, que permiten su uso por ejemplo como pavimento o revestimiento tanto en interior como en zonas de exterior. Además, posee un elevado módulo de rotura (alta resistencia mecánica) y tenacidad, con unas resistencias mecánicas a flexión típicamente entre 250 y 500 kg/cm2. To obtain porcelain stoneware, it is based on a composition based on natural raw materials such as: kaolin (or kaolinitic clay), quartz and feldspar. Porcelain stoneware is a ceramic product that is vitrified throughout its mass and is very compact, which has as its essential characteristic a low and closed porosity. This material has excellent mechanical and chemical properties, which allow its use, for example, as flooring or cladding both indoors and outdoors. In addition, it has a high modulus of breakage (high mechanical strength) and toughness, with mechanical flexural strengths typically between 250 and 500 kg / cm 2 .
Un producto vitrificado tipo porcelana está caracterizado por poseer una microestructura que combina una matriz vitrea en la que se localizan diferentes fases cristalinas. Las fases cristalinas más comunes que se encuentran en el gres sinterizado son cuarzo, mullita, alúmina, zircón, anortita y ganhita. Mientras que ciertas fases cristalinas proceden de los productos de partida, otras son consecuencias de reacciones químicas que tienen lugar a alta temperatura durante el tratamiento térmico. A porcelain-type vitrified product is characterized by having a microstructure that combines a vitreous matrix in which different crystalline phases are located. The most common crystalline phases found in sintered stoneware are quartz, mullite, alumina, zircon, anortite and ganhite. While certain crystalline phases come from the starting products, others are consequences of chemical reactions that take place at high temperature during heat treatment.
El gres porcelánico requiere un proceso cerámico bien conocido y que corresponde a un proceso tecnológicamente maduro que consiste, a grandes rasgos, en obtener una mezcla homogénea de materias primas, conformar la pieza y realizar un tratamiento térmico a temperaturas superiores a 1 100°C. Porcelain stoneware requires a well-known ceramic process that corresponds to a technologically mature process that consists, in broad strokes, of obtaining a homogeneous mixture of raw materials, forming the part and performing a heat treatment at temperatures above 1 100 ° C.
Aunque se forma mullita nanocristalina, la proporción de alúmina aportada por las materias primas empleadas en la fabricación de gres porcelánico, tales como las arcillas caoliníticas, cuarzo y feldespatos, no supera el 15% en peso y por tanto la proporción de mullita es muy limitada. La solución consistente en la incorporación de productos sintéticos como AI2O3 resulta inviable desde el punto de vista económico. Although nanocrystalline mullite is formed, the proportion of alumina contributed by the raw materials used in the manufacture of porcelain stoneware, such as kaolinitic clays, quartz and feldspars, does not exceed 15% by weight and therefore the proportion of mullite is very limited . The solution consisting of the incorporation of synthetic products such as AI2O3 is economically unfeasible.
Otra de las fases que contribuyen notablemente al refuerzo mecánico de la matriz del gres porcelánico es el cuarzo, polimorfismo de S1O2. La presencia de cuarzo en el gres porcelánico se produce como consecuencia de la incorporación de dicha fase en forma de arenas silíceas. Los cristales de cuarzo además aportan excelente propiedades de resistencia al desgaste. Sin embargo, el porcentaje de cuarzo en una composición de porcelánico está limitado por generar problemas de conformado eficiente de piezas, en particular si se trata de grandes formatos. Another phase that contributes significantly to the mechanical reinforcement of the porcelain stoneware matrix is quartz, polymorphism of S1O2. The presence of quartz in porcelain stoneware occurs as a result of the incorporation of said phase in the form of siliceous sands. The quartz crystals also provide excellent wear resistance properties. However, the percentage of quartz in a porcelain composition is limited by generating problems of efficient forming of parts, particularly if they are large formats.
El empleo de piezas de gran formato requiere de una mejora en la respuesta mecánica de las piezas, en concreto en el módulo de rotura a flexión. El gres porcelánico se encuentra limitado a valores típicamente comprendidos entre 250 y 500 kg/cm2, y por tanto, la producción de piezas cerámicas con prestaciones superiores es económicamente inviable. Una solución técnica empleada para generar piezas de gran formato consiste en el aumento del espesor de las piezas, pero obviamente implica un mayor consumo de materias primas, así como un mayor consumo de energía en el procesado y un mayor peso por m2 del material. The use of large-format parts requires an improvement in the mechanical response of the parts, specifically in the flexural rupture module. Porcelain stoneware is limited to values typically between 250 and 500 kg / cm 2 , and therefore, the production of ceramic pieces with superior performance is economically unfeasible. A technical solution used to generate large-format parts consists in increasing the thickness of the pieces, but obviously it implies a higher consumption of raw materials, as well as a greater consumption of energy in the processing and a greater weight per m 2 of the material.
Por tanto, se necesita un nuevo gres porcelánico con propiedades mejoradas, en especial un gres porcelánico con propiedades mecánicas reforzadas. DESCRIPCIÓN DE LA INVENCIÓN Therefore, a new porcelain tile with improved properties is needed, in special a porcelain stoneware with reinforced mechanical properties. DESCRIPTION OF THE INVENTION
La presente invención presenta las siguientes ventajas respecto a los productos de gres porcelánico presentes en el estado de la técnica: The present invention has the following advantages over the porcelain stoneware products present in the state of the art:
- presenta una mayor dureza y resistencia - presents a greater hardness and resistance
- tiene la posibilidad de reducir el espesor de las piezas de gres porcelánico manteniendo las propiedades mecánicas exigibles a las piezas, lo que permite disminuir el peso de las piezas en aquellas aplicaciones en las que resulte una limitación, en particular en las piezas de grandes dimensiones denominadas piezas de gran formato, - It has the possibility of reducing the thickness of the porcelain stoneware pieces while maintaining the mechanical properties required of the pieces, which makes it possible to reduce the weight of the pieces in those applications where a limitation results, particularly in large pieces called large format pieces,
- Los minerales de hierro y magnesio que se emplean son minerales muy abundantes en la naturaleza. - The iron and magnesium minerals used are very abundant minerals in nature.
Un primer aspecto de la presente invención se refiere a un gres porcelánico que comprende cristales de silicatos seleccionados de la lista que comprende silicatos de magnesio, silicatos de hierro y silicatos de magnesio y hierro, preferentemente silicatos de hierro y magnesio, donde los cristales están homogéneamente distribuidos y tienen un tamaño medio de 20nm a 1000nm, preferiblemente de 50 a 500nm y más preferiblemente de 80 a 200 nm. A first aspect of the present invention relates to a porcelain stoneware comprising silicate crystals selected from the list comprising magnesium silicates, iron silicates and magnesium and iron silicates, preferably iron and magnesium silicates, where the crystals are homogeneously distributed and have an average size of 20 nm to 1000 nm, preferably 50 to 500 nm and more preferably 80 to 200 nm.
Un segundo aspecto de la presente invención se refiere al procedimiento de obtención del gres porcelánico tal y como se ha descrito anteriormente que comprende las etapas de: a) mezclado en medio acuoso de: i) al menos una arcilla plástica en una proporción de 40% a 70% en peso, A second aspect of the present invention relates to the process for obtaining porcelain stoneware as described above, comprising the steps of: a) mixing in aqueous medium of: i) at least one plastic clay in a proportion of 40% to 70% in weight,
ii) al menos un mineral de hierro, magnesio o ambos en una proporción de 10% a 40% en peso,  ii) at least one iron ore, magnesium or both in a proportion of 10% to 40% by weight,
iii) al menos una arena en una proporción de 5% a 30% en peso, y iv) al menos un feldespato en una proporción de 0,5% a 10% en peso. b) secado del producto obtenido en la etapa anterior c) conformado de piezas del producto obtenido en la etapa anterior d) cocer la mezcla resultante de la etapa anterior  iii) at least one sand in a proportion of 5% to 30% by weight, and iv) at least one feldspar in a proportion of 0.5% to 10% by weight. b) drying of the product obtained in the previous stage c) forming parts of the product obtained in the previous stage d) baking the mixture resulting from the previous stage
Además, un tercer aspecto de la presente invención se refiere al uso del gres porcelánico tal y como se ha descrito anteriormente como pieza de recubrimiento o decorativa para suelos, paredes, fachadas, mobiliario o sanitarios. In addition, a third aspect of the present invention relates to the use of porcelain stoneware as described above as a cover or decorative piece for floors, walls, facades, furniture or sanitary ware.
Definiciones Definitions
Por "gres porcelánico" se entiende un material cerámico duro, vitrificado en toda su masa y muy compacto, que presenta como característica esencial una porosidad baja y cerrada, propiedades mecánicas como resistencia a la rotura y resistencia al desgaste, resistente al ataque químico y prácticamente impermeable. Para su obtención se parte de una composición basada en materias primas naturales como son la arcilla, el cuarzo y el feldespato. By "porcelain stoneware" is meant a hard ceramic material, vitrified in all its mass and very compact, which presents as an essential characteristic a low and closed porosity, mechanical properties such as resistance to breakage and wear resistance, resistant to chemical attack and practically waterproof. To obtain it, it is based on a composition based on natural raw materials such as clay, quartz and feldspar.
Por el término "cristales de silicatos" se entiende un sólido homogéneo que presenta una estructura interna ordenada de sus partículas reticulares, cuya composición química comprende grupos SiOx. The term "silicate crystals" means a homogeneous solid that has an ordered internal structure of its reticular particles, the chemical composition of which comprises SiO x groups.
Una "arcilla plástica" es una arcilla que forma una masa moldeable cuando se mezcla con agua. Por arcilla se entiende silicatos de aluminios hidratados, procedentes de la descomposición de minerales de aluminio. De las diferentes variedades de arcillas plásticas se consideran las arcillas tipo caolinita, esmectita e illita. A "plastic clay" is a clay that forms a moldable mass when mixed with water. By clay is meant hydrated aluminum silicates, from the decomposition of aluminum ores. Of the different varieties of plastic clays, kaolinite, smectite and illite clays are considered.
Por el término "mineral de hierro, magnesio o hierro y magnesio" se entiende una sustancia química sólida formada por procesos biogeoquímicos que tiene una composición química característica (pero variable dentro de unos límites y una estructura atómica ordenada que comprende cationes de hierro, magnesio o hierro y magnesio respectivamente. The term "iron ore, magnesium or iron and magnesium" means a solid chemical substance formed by biogeochemical processes that has a characteristic chemical composition (but variable within limits and an orderly atomic structure comprising cations of iron, magnesium or iron and magnesium respectively.
Una "arena" o "arena cuarcítica" es un material sedimentario no consolidado presente en la naturaleza con un tamaño de partícula comprendido entre 0,2 μιη y 5000 μιτι comprendida mayoritariamente por partículas cristalinas de S1O2, generalmente en su variedad polimórfica de cuarzo. A "sand" or "quartzite sand" is an unconsolidated sedimentary material present in nature with a particle size between 0.2 μιη and 5000 μιτι comprised mostly of crystalline particles of S1O2, generally in its polymorphic variety of quartz.
Por el término "feldespato" se entiende un grupo de minerales de que comprende silicatos de aluminio y de calcio como la anortita, de fórmula general CaAl2SÍ20s, o silicatos de sodio como la albita de fórmula general NaAISi308, o silicatos de potasio como el feldespato potásico de fórmula general KAIS1O3O8, o mezclas de estas bases. The term "feldspar" means a group of minerals comprising aluminum and calcium silicates such as anortite, of general formula CaAl2SÍ20s, or sodium silicates such as albite of general formula NaAISi 3 0 8 , or potassium silicates such as potassium feldspar of general formula KAIS1O3O8, or mixtures of these bases.
Por el término "cocer" se entiende someter a un tratamiento térmico que comprende temperaturas elevadas, preferiblemente temperaturas superiores a 500°C. By the term "baking" is meant to undergo a heat treatment comprising high temperatures, preferably temperatures above 500 ° C.
Por "pieza de recubrimiento o decorativa" se entiende una pieza utilizada en construcción que permite recubrir una superficie, ya sea horizontal o vertical, interior o exterior, recta o curva. "Coating or decorative piece" means a piece used in construction that allows a surface to be coated, whether horizontal or vertical, interior or exterior, straight or curved.
Descripción detallada de la invención Detailed description of the invention
Un primer aspecto de la presente invención se refiere a un gres porcelánico que comprende cristales de silicatos seleccionados de la lista que comprende silicatos de magnesio, silicatos de hierro o silicatos de magnesio y hierro, preferentemente silicatos de hierro y magnesio, donde los cristales están homogéneamente distribuidos y tienen un tamaño medio de 20nm a 1000nm, preferiblemente de 50nm a 500nm y más preferiblemente de 80nm a 200 nm. A first aspect of the present invention relates to a porcelain tile that it comprises silicate crystals selected from the list comprising magnesium silicates, iron silicates or magnesium and iron silicates, preferably iron and magnesium silicates, where the crystals are homogeneously distributed and have an average size of 20nm to 1000nm, preferably 50nm at 500 nm and more preferably from 80 nm to 200 nm.
En una realización preferida del gres porcelánico de la invención, los cristales de silicatos pertenecen al grupo mineral olivino. Por "grupo mineral olivino", también llamado peridoto, se entiende un nesosilicato de magnesio y hierro. El grupo olivino comprende en sus extremos los minerales fayalita (silicato de hierro) y forsterita (silicato de magnesio) así como las composiciones intermedias (silicatos de hierro y magnesio). Estos minerales cristalizan en el grupo cristalino ortorrómbico. In a preferred embodiment of the porcelain stoneware of the invention, the silicate crystals belong to the olivine mineral group. By "olivine mineral group", also called peridot, is a magnesium and iron nesosilicate. The olivine group comprises at its ends the minerals Fayalite (iron silicate) and forsterite (magnesium silicate) as well as the intermediate compositions (iron and magnesium silicates). These minerals crystallize in the orthorhombic crystalline group.
Los cristales de silicatos obtenidos están además caracterizados por encontrarse de manera abundante y con una buena dispersión en la matriz vitrea del gres porcelánico. Estos cristales producen un refuerzo mecánico del gres porcelánico. La distribución y dispersión de dichas fases cristalinas permite un reforzamiento de la matriz vitrea y contribuye a los mecanismos de deflexión de grieta. Estas fases se consiguen empleando materias primas con un contenido importante en cationes de hierro y magnesio. En los productos de gres porcelánico del estado de la técnica estos cationes se evitan porque generan coeficientes de dilatación elevados, que dificultan el correcto acoplamiento de los esmaltes sobre dichas piezas e impiden el esmaltado de las piezas. Sin embargo, la dimensión submicrónica y en particular la dimensión nanométrica de las cristalizaciones de las fases desarrolladas en la presente invención permite mantener el coeficiente de dilatación del gres porcelánico resultante en valores estándar para su producción. Por lo tanto, las fases nanométricas permiten no solo reforzar mecánicamente sino también mantener los coeficientes de dilatación en valores adecuados para el esmaltado de las piezas. Así, los materiales de la presente invención presentan una ventaja frente a aquellos que se encuentran en el estado de la técnica debido a un efecto de reforzamiento mecánico. En otra realización preferida del primer aspecto de la presente invención, el gres porcelánico además comprende cristales de cuarzo, donde los cristales de cuarzo tienen un tamaño medio de 0,5 m a 100 μιη, preferiblemente de 1 μιη a 40 μιη y más preferiblemente de 2 μιη a 20 μιη. Los granos de cuarzo están caracterizados por presentar bordes con formas redondeadas que indican una disolución parcial en la fase vitrea y una buena integración en la misma. Estos cristales actúan favorablemente desde el punto de vista mecánico, pues refuerzan la matriz vitrea por diferencias en coeficientes de dilatación. The silicate crystals obtained are also characterized by being abundantly and with a good dispersion in the vitreous matrix of the porcelain stoneware. These crystals produce a mechanical reinforcement of porcelain stoneware. The distribution and dispersion of said crystalline phases allows a reinforcement of the vitreous matrix and contributes to the crack deflection mechanisms. These phases are achieved using raw materials with an important content in iron and magnesium cations. In the porcelain stoneware products of the prior art, these cations are avoided because they generate high expansion coefficients, which hinder the correct coupling of the enamels on said pieces and prevent the enamelling of the pieces. However, the submicronic dimension and in particular the nanometric dimension of the crystallizations of the phases developed in the present invention allows to maintain the expansion coefficient of the resulting porcelain stoneware in standard values for its production. Therefore, the nanometric phases allow not only to mechanically reinforce but also maintain the expansion coefficients in values suitable for the enamelling of the pieces. Thus, the materials of the present invention have an advantage over those in the state of the art due to a mechanical reinforcing effect. In another preferred embodiment of the first aspect of the present invention, the porcelain stoneware further comprises quartz crystals, where the quartz crystals have an average size of 0.5 m to 100 μιη, preferably 1 μιη to 40 μιη and more preferably 2 μιη to 20 μιη. Quartz grains are characterized by rounded edges that indicate a partial dissolution in the vitreous phase and a good integration in it. These crystals act favorably from the mechanical point of view, as they reinforce the vitreous matrix by differences in coefficients of expansion.
Así, el gres porcelánico de la presente invención comprende cristalizaciones correspondientes a fases cristalinas de cuarzo y fases cristalinas tipo olivino. Thus, the porcelain stoneware of the present invention comprises crystallizations corresponding to crystalline quartz phases and olivine crystalline phases.
En otra realización preferida del primer aspecto de la presente invención, el gres porcelánico además comprende cristales de indialita en una proporción menor al 10%, preferiblemente menor al 5% y más preferiblemente menor a 2%. Por "indialita" se entiende un ciclosilicato de aluminio y hierro y magnesio, que es un polimorfo a alta temperatura de la cordierita. Los ciclosilicatos son silicatos que tienen tetraedros enlazados, con una ratio Si:0 1 :3. Su formación en una porcelana produce cristales de tamaño microcristalino, reduce las propiedades mecánicas del gres porcelánico y disminuye notablemente el coeficiente térmico de expansión. In another preferred embodiment of the first aspect of the present invention, the porcelain stoneware further comprises indialite crystals in a proportion less than 10%, preferably less than 5% and more preferably less than 2%. By "indialite" is meant an aluminum and iron and magnesium cyclosilicate, which is a high temperature polymorph of cordierite. Cyclosilicates are silicates that have bound tetrahedra, with a Si: 0 1: 3 ratio. Its formation in a porcelain produces crystals of microcrystalline size, reduces the mechanical properties of porcelain stoneware and significantly decreases the thermal coefficient of expansion.
En otra realización preferida del primer aspecto de la presente invención, la proporción de Mg, expresada en porcentaje en peso del óxido equivalente respecto al peso total, es de 8% a 22%, preferiblemente de 10% a 20% y más preferiblemente de 12% a 16% In another preferred embodiment of the first aspect of the present invention, the proportion of Mg, expressed as a percentage by weight of the equivalent oxide with respect to the total weight, is 8% to 22%, preferably 10% to 20% and more preferably 12 % to 16%
En otra realización preferida del primer aspecto de la presente invención, la proporción de Fe, expresada en porcentaje en peso del óxido equivalente respecto al peso total, es de 2% a 15%, preferiblemente de 3% a 10% y más preferiblemente de 4% a 6% En otra realización preferida del primer aspecto de la presente invención, el gres porcelánico además comprende unas proporciones de Si, expresada en porcentaje en peso del óxido equivalente respecto al total, es de un 40% a 70%, preferiblemente de 45% a 62% y más preferiblemente de 50% a 56%. In another preferred embodiment of the first aspect of the present invention, the proportion of Fe, expressed as a percentage by weight of the equivalent oxide with respect to the total weight, is from 2% to 15%, preferably from 3% to 10% and more preferably from 4 % to 6% In another preferred embodiment of the first aspect of the present invention, the porcelain stoneware further comprises Si proportions, expressed as a percentage by weight of the oxide equivalent to the total, is 40% to 70%, preferably 45% to 62% and more preferably from 50% to 56%.
En otra realización preferida del primer aspecto de la presente invención, el gres porcelánico además comprende unas proporciones de Al, expresada en porcentaje en peso del óxido equivalente respecto al total, es de un 5% a 22%, preferiblemente de 8% a 20% y más preferiblemente de 12% a 18%. In another preferred embodiment of the first aspect of the present invention, the porcelain stoneware also comprises proportions of Al, expressed as a percentage by weight of the oxide equivalent to the total, is 5% to 22%, preferably 8% to 20% and more preferably from 12% to 18%.
En otra realización preferida del primer aspecto de la presente invención, el gres porcelánico además comprende Na, K y Ca en proporciones inferiores a 5% expresadas en porcentaje en peso de los respectivos óxidos equivalente respecto al peso total. In another preferred embodiment of the first aspect of the present invention, the porcelain stoneware further comprises Na, K and Ca in proportions of less than 5% expressed as a percentage by weight of the respective equivalent oxides with respect to the total weight.
En otra realización preferida del primer aspecto de la presente invención, el gres porcelánico además comprende otros compuestos minoritarios en una proporción inferior al 1 % en peso respecto del total de la composición. In another preferred embodiment of the first aspect of the present invention, the porcelain stoneware further comprises other minor compounds in a proportion less than 1% by weight with respect to the total composition.
La presente invención permite adaptar la formulación para el desarrollo de composiciones de gres porcelánico con diferentes coeficientes de dilatación y diferentes temperaturas de sinterización. The present invention allows to adapt the formulation for the development of porcelain stoneware compositions with different expansion coefficients and different sintering temperatures.
Otras cristalizaciones que se pueden incorporar en el gres porcelánico son cristales de circón, corindón, espinelas, granates. El efecto de estas otras cristalizaciones está relacionado principalmente con la modificación cromática del gres porcelánico de la presente invención. Los procedimientos de modificación cromática del gres porcelánico mediante partículas cristalizadas compatibles con la fase vitrea del gres porcelánico están sobradamente descritos en el estado de la técnica. Other crystallizations that can be incorporated into porcelain stoneware are zircon crystals, corundum, spinels, garnets. The effect of these other crystallizations is mainly related to the chromatic modification of the porcelain stoneware of the present invention. The methods of chromatic modification of the porcelain stoneware by crystallized particles compatible with the vitreous phase of the porcelain stoneware are well described in the state of the art.
En otra realización preferida del primer aspecto de la presente invención, la densidad del gres porcelánico es de al menos 2,4 g/cm3, preferente al menos 2,5 g/cm3. In another preferred embodiment of the first aspect of the present invention, the Porcelain stoneware density is at least 2.4 g / cm 3 , preferably at least 2.5 g / cm 3 .
Asimismo, los materiales sinterizados presentan porosidad cerrada y un coeficiente de adsorción de agua inferior a 0,5%. El coeficiente de expansión térmica en el intervalo 50-300°C es inferior a 70x10"7oC"1, preferentemente inferior a 60x10"7oC"1. El coeficiente de dilatación se mantiene en valores adecuados debido a la naturaleza y tamaño de las fases formadas. Además tal y como se ha indicado previamente, los productos de gres porcelánico de la presente invención presentan una buena resistencia mecánica, con módulos de resistencia mecánica a la flexión de al menos 800 kg/cm2 y preferentemente de al menos 1000 kg/cm2. La resistencia mecánica al impacto determinada por medio del coeficiente de restitución mediante la norma ISO 10545-5:1996 en las muestras de gres porcelánico de la presente invención alcanza valores de 0,80 y preferentemente de 0,85 que resultan ventajosos frente a los coeficientes de restitución para los materiales de gres porcelánico en el estado de la técnica, que son inferiores a 0,70. Un mayor coeficiente de restitución implica una mayor resistencia al impacto. Also, sintered materials have closed porosity and a water adsorption coefficient of less than 0.5%. The coefficient of thermal expansion in the range 50-300 ° C is less than 70x10 "7o C " 1 , preferably less than 60x10 "7o C " 1 . The expansion coefficient is maintained at adequate values due to the nature and size of the phases formed. In addition, as previously indicated, the porcelain stoneware products of the present invention have a good mechanical strength, with modules of mechanical flexural strength of at least 800 kg / cm 2 and preferably of at least 1000 kg / cm 2 . The mechanical impact resistance determined by means of the restitution coefficient by means of ISO 10545-5: 1996 in the porcelain stoneware samples of the present invention reaches values of 0.80 and preferably 0.85 which are advantageous against the coefficients. of restitution for porcelain stoneware materials in the state of the art, which are less than 0.70. A higher coefficient of restitution implies greater impact resistance.
En otra realización preferida de la presente invención, el gres porcelánico además comprende una capa de engobe. Por "engobe" se entiende una capa que recubre la cara vista de la pieza de gres porcelánico, preferiblemente compuesta de arcillas claras, y que tiene como fin hacer opaca y blanquear la superficie del gres porcelánico, solventando así las limitaciones que pueda producirse por la coloración en superficie del gres porcelánico de la presente invención. In another preferred embodiment of the present invention, the porcelain stoneware further comprises a slip layer. By "engobe" is meant a layer that covers the exposed face of the piece of porcelain stoneware, preferably composed of light clays, and whose purpose is to make the surface of the porcelain stoneware opaque and whiten, thus solving the limitations that may arise from the surface coloring of the porcelain stoneware of the present invention.
En otra realización preferida de la presente invención, el gres porcelánico además comprende una capa de esmalte. Por "esmalte" se entiende un material vitreo que se aplica para adornar y colorear la pieza de gres porcelánico. El esmalte es el resultado de la fusión de cristal en polvo a través de un proceso de calentamiento. En el proceso de esmaltado el soporte se recubre por una capa de esmalte que puede estar decorada con pigmentos cerámicos. Esta capa de esmalte se puede aplicar sobre superficies de gres porcelánico previamente recubiertas o no por una capa de engobe. Esto elimina las limitaciones que podían derivarse del color de las piezas para los procesos de decoración en superficie. In another preferred embodiment of the present invention, the porcelain stoneware further comprises an enamel layer. "Enamel" means a vitreous material that is applied to decorate and color the piece of porcelain stoneware. Enamel is the result of the melting of powdered glass through a heating process. In the enamelling process the support is covered by a layer of enamel that can be decorated with ceramic pigments. This layer of Enamel can be applied on porcelain stoneware surfaces previously coated or not by a layer of engobe. This eliminates the limitations that could be derived from the color of the pieces for surface decoration processes.
Un segundo aspecto de la presente invención se refiere al procedimiento de obtención del gres porcelánico tal y como se ha descrito anteriormente que comprende las etapas de: a) mezclado en medio acuoso de: i) al menos una arcilla plástica en una proporción de 40% a 70% en peso, A second aspect of the present invention relates to the process for obtaining porcelain stoneware as described above, comprising the steps of: a) mixing in aqueous medium of: i) at least one plastic clay in a proportion of 40% at 70% by weight,
ii) al menos un mineral de hierro, magnesio o ambos en una proporción de 10% a 40% en peso,  ii) at least one iron ore, magnesium or both in a proportion of 10% to 40% by weight,
iii) al menos una arena en una proporción de 5% a 30% en peso, y iv) al menos un feldespato en una proporción de 0,5% a 10% en peso. b) secado del producto obtenido en la etapa anterior c) conformado de piezas del producto obtenido en la etapa anterior d) cocer la mezcla resultante de la etapa anterior  iii) at least one sand in a proportion of 5% to 30% by weight, and iv) at least one feldspar in a proportion of 0.5% to 10% by weight. b) drying of the product obtained in the previous stage c) forming parts of the product obtained in the previous stage d) baking the mixture resulting from the previous stage
En una realización preferida del segundo aspecto de la presente invención, la arcilla plástica comprende filosilicatos. Dentro de las arcillas plásticas se pueden distinguir dos tipologías de arcillas para la producción de gres porcelánico: arcillas para pastas blancas y arcillas para pastas rojas. Las arcillas para pastas blancas son minerales arcillosos asociados a los tipos de ball clay o China clay, de naturaleza illítico-caolinítica o caolinítica. Las arcillas para pastas blancas están caracterizadas por la aportación de alúmina de la composición y por poseer un bajo contenido en cationes de hierro. Las arcillas para pastas rojas son minerales arcillosos de naturaleza illítico-clorita o illítico-caolinita. Las arcillas para pastas rojas poseen contenidos importantes de cationes de hierro que les confieren el característico color rojizo. Los filosilicatos son preferiblemente de naturaleza illítico-caolinítica o caolinítica.o illítico-clorita. In a preferred embodiment of the second aspect of the present invention, the plastic clay comprises phyllosilicates. Within the plastic clays two types of clays can be distinguished for the production of porcelain stoneware: clays for white pastes and clays for red pastes. Clays for white pastes are clay minerals associated with the types of ball clay or China clay, of an illicit-kaolinitic or kaolinitic nature. Clays for white pasta are characterized by the contribution of alumina of the composition and for having a low content in iron cations. Clays for red pasta are clay minerals of an illicit-chlorite or illitic-kaolinite nature. Clays for red pasta have important contents of iron cations that give them the characteristic reddish color. Philosilicates are preferably of an illitic-kaolinitic or kaolinitic nature. Or illitic-chlorite.
En otra realización preferida del segundo aspecto de la presente invención, la arena o arena cuarcítica comprende partículas cristalinas de cuarzo. El cuarzo es un mineral compuesto de dióxido de silicio conocido como sílice, Si02, ampliamente descrito y conocido en el estado de la técnica y que posee una dureza elevada. In another preferred embodiment of the second aspect of the present invention, the quartzitic sand or sand comprises crystalline quartz particles. Quartz is a mineral composed of silicon dioxide known as silica, Si0 2 , widely described and known in the state of the art and having a high hardness.
En otra realización preferida del segundo aspecto de la presente invención, el feldespato comprende un grupo de minerales tectosilicatos que se encuentran constituidos fundamentalmente por rocas de tipo ígneo. In another preferred embodiment of the second aspect of the present invention, the feldspar comprises a group of tectosilicate minerals that are constituted primarily of igneous type rocks.
En otra realización preferida del segundo aspecto de la presente invención, el mineral de hierro, magnesio o ambos es un nesosilicato, preferiblemente del grupo olivino. Dichos minerales de hierro y magnesio son preferiblemente de origen magmático. Estos minerales forman parte de dunitas y peridotitas, o se asocian a fases de tipo piroxenos y cromitas. Además son el componente mineral principal en gabros, basaltos y kimberlitas. Así mismo puede estar en combinación entre otros con silicatos como cloritas, talcos y brucitas. In another preferred embodiment of the second aspect of the present invention, the iron ore, magnesium or both is a nesosilicate, preferably of the olivine group. Said iron and magnesium minerals are preferably of magmatic origin. These minerals are part of dunites and peridotites, or are associated with pyroxene and chromite-like phases. They are also the main mineral component in gabros, basalts and kimberlites. It can also be in combination with silicates such as chlorites, talcs and brucites.
En otra realización preferida del segundo aspecto de la presente invención, la proporción de Mg, expresada en porcentaje en peso del óxido equivalente respecto al peso total es de 8% a 22%, preferiblemente de 10% a 20% y más preferiblemente de 12% a 16% In another preferred embodiment of the second aspect of the present invention, the proportion of Mg, expressed as a percentage by weight of the equivalent oxide with respect to the total weight is 8% to 22%, preferably 10% to 20% and more preferably 12% at 16%
En otra realización preferida del segundo aspecto de la presente invención, la proporción de Fe, expresada en porcentaje en peso del óxido equivalente respecto al peso total es de 2% a 15%, preferiblemente de 3% a 10% y más preferiblemente de 4% a 6% In another preferred embodiment of the second aspect of the present invention, the proportion of Fe, expressed as a percentage by weight of the equivalent oxide with respect to the total weight it is from 2% to 15%, preferably from 3% to 10% and more preferably from 4% to 6%
En otra realización preferida del segundo aspecto de la presente invención, la proporción de Si, expresada en porcentaje en peso del óxido equivalente respecto al total, es de un 40% a 70%, preferiblemente de 45% a 62% y más preferiblemente de 50% a 56%. In another preferred embodiment of the second aspect of the present invention, the proportion of Si, expressed as a percentage by weight of the equivalent oxide with respect to the total, is 40% to 70%, preferably 45% to 62% and more preferably 50 % to 56%.
En otra realización preferida del segundo aspecto de la presente invención, la proporción de Al, expresada en porcentaje en peso del óxido equivalente respecto al total, es de un 5% a 22%, preferiblemente de 8% a 20% y más preferiblemente de 12% a 18%. In another preferred embodiment of the second aspect of the present invention, the proportion of Al, expressed as a percentage by weight of the equivalent oxide with respect to the total, is 5% to 22%, preferably 8% to 20% and more preferably 12 % to 18%.
En otra realización preferida del segundo aspecto de la presente invención, las proporciones de Na,In another preferred embodiment of the second aspect of the present invention, the proportions of Na,
K y Ca expresadas en porcentaje en peso de los respectivos óxidos equivalente respecto al peso total inferiores a 5%. K and Ca expressed as a percentage by weight of the respective oxides equivalent to the total weight of less than 5%.
En otra realización preferida del segundo aspecto de la presente invención, el procedimiento además comprende una etapa (a1 ) posterior a (a) y anterior a (b) de adición de al menos un aditivo, donde el aditivo se selecciona de la lista que comprende defloculates, dispersantes, antiespumantes, bactericidas, aglomerantes, plastificantes y ceras. Un "defloculante" es una sustancia química que evita la agregación de partículas sólidas en una dispersión coloidal, como por ejemplo el silicato sódico. Un "dispersante" es un aditivo que se utiliza para lograr que un soluto tenga distribución y dispersión en un disolvente, como por ejemplo tripolifosfato, pirofosfato tetrasódico, poliacrilato amónico y poliacrilato sódico. Un "antiespumante" es una sustancia que reduce la tensión superficial de la suspensión y previene la aparición de espumas durante el mezclado, como por ejemplo un poliéster de siloxano. Un "bactericida" es una sustancia que impide la proliferación de bacterias en la preparación del gres porcelánico. Ejemplos de sustancias bactericidas adecuadas son las aminas cuaternarias. Un "aglomerante" es una sustancia química que tiene la capacidad de aglomerar o unir fragmentos o partículas, como por ejemplo emulsiones acrílicas suspendidas en agua, látex acrílico de estireno, un polivinilalcohol o un polímero de metilcelulosa. Un "plastificante" es una sustancia de tipo resina o polimérica que confiere plasticidad a la masa cerámica en verde, en particular bajo deformación por presión, como por ejemplo el polietileno glicol. Una cera es un compuesto químico orgánico maleable. Las ceras sintéticas comprenden alcanos de elevado peso molecular, como las parafinas. Las ceras naturales son ésteres de ácidos grasos con alcoholes de peso molecular elevado, como por ejemplo cera de abeja. Aglomerantes, plastificantes y ceras se utilizan especialmente cuando el procedimiento comprende una etapa de extrudido. In another preferred embodiment of the second aspect of the present invention, the method further comprises a step (a1) after (a) and before (b) adding at least one additive, wherein the additive is selected from the list comprising defloculates, dispersants, defoamers, bactericides, binders, plasticizers and waxes. A "deflocculant" is a chemical that prevents the aggregation of solid particles in a colloidal dispersion, such as sodium silicate. A "dispersant" is an additive that is used to make a solute have distribution and dispersion in a solvent, such as tripolyphosphate, tetrasodium pyrophosphate, ammonium polyacrylate and sodium polyacrylate. An "antifoam" is a substance that reduces the surface tension of the suspension and prevents the appearance of foams during mixing, such as a siloxane polyester. A "bactericide" is a substance that prevents the proliferation of bacteria in the preparation of porcelain stoneware. Examples of suitable bactericidal substances are quaternary amines. A "binder" is a chemical that has the ability to agglomerate or bind fragments or particles, such as acrylic emulsions suspended in water, acrylic styrene latex, a polyvinyl alcohol or a methylcellulose polymer. A "plasticizer" is a resin or polymeric substance that confers plasticity to the green ceramic mass, in particular under pressure deformation, such as polyethylene glycol. A wax is a malleable organic chemical compound. Synthetic waxes comprise high molecular weight alkanes, such as paraffins. Natural waxes are fatty acid esters with high molecular weight alcohols, such as beeswax. Binders, plasticizers and waxes are especially used when the process comprises an extruded step.
En otra realización preferida del segundo aspecto de la presente invención, el procedimiento además comprende una etapa (a2) anterior a (b) de homogeneización por molienda o dispersión del producto obtenido en la etapa anterior. Para la preparación de la suspensión cerámica o barbotina que permite homogeneizar la composición se pueden emplear sistemas habituales de la industria cerámica, como son molienda o dispersión. El tamaño promedio de partícula de la barbotina de homogeneización de las materias primas de gres porcelánico de la presente composición será tal que el d90 (diámetro equivalente promedio al 90% de la distribución) sea inferior a 100 μιη. In another preferred embodiment of the second aspect of the present invention, the method further comprises a step (a2) prior to (b) homogenization by grinding or dispersion of the product obtained in the previous stage. For the preparation of the ceramic suspension or slip that allows the composition to be homogenized, conventional systems of the ceramic industry can be used, such as grinding or dispersion. The average particle size of the homogenization slip of the porcelain stoneware raw materials of the present composition will be such that the d90 (average equivalent diameter at 90% of the distribution) is less than 100 μιη.
En otra realización preferida del segundo aspecto de la presente invención, el secado se lleva a cabo por atomizado. In another preferred embodiment of the second aspect of the present invention, drying is carried out by spraying.
En otra realización preferida del segundo aspecto de la presente invención, la etapa de conformado de piezas se lleva a cabo por prensado uniaxial, prensado isostático, o extrudido de cuerpos cerámicos en verde. La mezcla homogénea de materias primas se seca mediante procesos de atomizado para obtener una distribución de aglomerados adecuada para el conformado de piezas mediante procesos convencionales como pueden ser entre otros el prensado uniaxial o el prensado isoestático. Adicionalmente, mediante la incorporación de una proporción adecuada de agua que se encuentre por encima del límite sólido de la formulación referida de la presente invención se puede conformar mediante extrudido de cuerpos cerámicos en verde. In another preferred embodiment of the second aspect of the present invention, the step of forming parts is carried out by uniaxial pressing, isostatic pressing, or extrusion of ceramic bodies in green. The homogeneous mixture of raw materials is dried by atomizing processes to obtain a distribution of agglomerates suitable for forming parts by conventional processes such as uniaxial pressing or isostatic pressing. Additionally, by incorporating a Adequate proportion of water that is above the solid limit of the referred formulation of the present invention can be formed by extruding ceramic bodies in green.
En otra realización preferida del segundo aspecto de la presente invención, el procedimiento además comprende una etapa (c1 ) posterior a (c) y anterior a (d) de aplicación del engobe. In another preferred embodiment of the second aspect of the present invention, the method further comprises a step (c1) subsequent to (c) and prior to (d) engobe application.
En otra realización preferida del segundo aspecto de la presente invención, el procedimiento además comprende una etapa (c2) anterior a (d) de esmaltado del producto resultante de la etapa anterior. Este esmaltado puede efectuarse sobre la pieza de gres porcelánico con o sin engobe. El proceso de esmaltado de las piezas con una capa de esmalte cerámico confiere a la baldosa cerámica propiedades técnicas y estéticas tales como: impermeabilidad, fácil limpieza, brillo, textura superficial, resistencia mecánica y química, así como amplias posibilidades de decoración. In another preferred embodiment of the second aspect of the present invention, the method further comprises a step (c2) prior to (d) enamelling of the product resulting from the previous stage. This enamelling can be done on the piece of porcelain stoneware with or without engobe. The enamelling process of the pieces with a layer of ceramic enamel gives the ceramic tile technical and aesthetic properties such as: impermeability, easy cleaning, gloss, surface texture, mechanical and chemical resistance, as well as extensive decoration possibilities.
En otra realización preferida del segundo aspecto de la presente invención, la cocción de la etapa (d) se lleva a cabo en ciclo industrial, preferentemente en monococción en un horno monoestrato de gas de cocción rápida. Preferentemente, la temperatura de la cocción de la etapa (d) está comprendida entre 980°C y 1280°C, aún más preferentemente entre 1 100°C y 1200°C. In another preferred embodiment of the second aspect of the present invention, the cooking of step (d) is carried out in an industrial cycle, preferably in monocoction in a fast-cooking single-layer gas oven. Preferably, the cooking temperature of step (d) is between 980 ° C and 1280 ° C, even more preferably between 1 100 ° C and 1200 ° C.
Las proporciones y el rango de temperatura se ajustan en función del contenido de cationes alcalino y alcalino-terreo de la composición. La modificación de la composición del gres porcelánico de la presente invención en función de las proporciones de componentes empleados representa así una ventaja ya que permite ajustar el rango de temperaturas en el que se obtienen materiales densificados. Este procedimiento resulta ventajoso dado que permite la obtención de productos cerámicos en procesos con diferentes temperaturas de cocción. Una ventaja adicional del procedimiento es que permite adaptarse a la disponibilidad de diferentes materias primas locales, limitando la dependencia con materias primas importadas. The proportions and temperature range are adjusted based on the alkali and alkaline earth earth cation content of the composition. The modification of the composition of the porcelain stoneware of the present invention depending on the proportions of components used thus represents an advantage since it allows adjusting the temperature range in which densified materials are obtained. This procedure is advantageous since it allows to obtain ceramic products in processes with different cooking temperatures. An additional advantage of the procedure is that it allows adapting to the availability of different local raw materials, limiting dependence on Imported raw materials.
En otra realización preferida del segundo aspecto de la presente invención, la cocción de la etapa (d) comprende ciclos rápidos de sinterización con tiempos de residencia a la máxima temperatura de los ciclos de entre 1 y 30 minutos, preferente entre 2 y 20 minutos y aún más preferentemente entre 3 y 10 minutos. Excelentes resultados se han obtenido cuando el tiempo de residencia a la máxima temperatura es de 6 minutos. Por "ciclo de sinterización" se entiende al ciclo térmico que se somete la formulación para que se formen las fases necesarias del gres porcelánico. El "tiempo de residencia a la máxima temperatura" es el tiempo que está la formulación sometida a la temperatura máxima del ciclo. Esta temperatura máxima está comprendida entre 980°C y 1280°C, preferiblemente entre 1 100°C y 1200°C. El tiempo total del ciclo térmico de cocción tiene una duración de entre 30 y 100 minutos, preferiblemente entre 40 y 80 minutos y aún más preferiblemente entre 45 y 60 minutos. La cocción se lleva a cabo preferiblemente bajo atmósfera oxidante. In another preferred embodiment of the second aspect of the present invention, the cooking of step (d) comprises rapid sintering cycles with residence times at the maximum temperature of the cycles of between 1 and 30 minutes, preferably between 2 and 20 minutes and even more preferably between 3 and 10 minutes. Excellent results have been obtained when the residence time at the maximum temperature is 6 minutes. By "sintering cycle" is meant the thermal cycle that the formulation undergoes so that the necessary phases of the porcelain stoneware are formed. The "residence time at maximum temperature" is the time that the formulation is subjected to the maximum temperature of the cycle. This maximum temperature is between 980 ° C and 1280 ° C, preferably between 1 100 ° C and 1200 ° C. The total time of the thermal cooking cycle lasts between 30 and 100 minutes, preferably between 40 and 80 minutes and even more preferably between 45 and 60 minutes. Cooking is preferably carried out under oxidizing atmosphere.
Un tercer aspecto de la presente invención se refiere al uso del gres porcelánico tal y como se ha descrito anteriormente como pieza de recubrimiento o decorativa en suelos, paredes, fachadas, mobiliario, sanitarios. Debido a la gran resistencia mecánica de los productos de gres porcelánico de la invención, en una realización preferida del tercer aspecto de la presente invención, la pieza es de gran formato. El término "gran formato" en el contexto de la invención significa formatos con superficies superiores a 0,20 m2, preferiblemente formatos superiores a 0,30 m2. A third aspect of the present invention relates to the use of porcelain stoneware as described above as a covering or decorative piece in floors, walls, facades, furniture, sanitary ware. Due to the high mechanical strength of the porcelain stoneware products of the invention, in a preferred embodiment of the third aspect of the present invention, the part is large format. The term "large format" in the context of the invention means formats with surfaces greater than 0.20 m 2 , preferably formats greater than 0.30 m 2 .
A lo largo de la descripción y las reivindicaciones la palabra "comprende" y sus variantes no pretenden excluir otras características técnicas, aditivos, componentes o pasos. Para los expertos en la materia, otros objetos, ventajas y características de la invención se desprenderán en parte de la descripción y en parte de la práctica de la invención. Los siguientes ejemplos se proporcionan a modo de ilustración, y no se pretende que sean limitativos de la presente invención. Throughout the description and the claims the word "comprises" and its variants are not intended to exclude other technical characteristics, additives, components or steps. For those skilled in the art, other objects, advantages and features of the invention will be derived partly from the description and partly from the practice of the invention. The following examples are provided by way of illustration, and are not intended to be limiting herein. invention.
BREVE DESCRIPCION DE LAS FIGURAS BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 . Difractograma de Rayos X en polvo de la muestra del ejemplo 1 . C: Cuarzo, F: Forsterita, E: Esteatita, M: Mullita, H: Hercinita; I: Intensidad; A: Ángulo 2Θ (grados). FIG. one . X-ray powder diffractogram of the sample of Example 1. C: Quartz, F: Forsterite, E: Soapstone, M: Mullite, H: Hercinite; I: Intensity; A: Angle 2Θ (degrees).
FIG. 2. Difractograma de Rayos X en polvo de la muestra del ejemplo 3. C: Cuarzo, F: Forsterita, E: Esteatita, M: Mullita, H: Hercinita; I: Intensidad; A: Ángulo 2Θ (grados) FIG. 2. X-ray powder diffractogram of the sample of Example 3. C: Quartz, F: Forsterite, E: Soapstone, M: Mullite, H: Hercinite; I: Intensity; A: Angle 2Θ (degrees)
FIG. 3. Micrografía de Microscopía Electrónica de Barrido (SEM) de la superficie pulida y atacada químicamente con ácido fluorhídrico correspondiente a la muestra del ejemplo 1 . FIG. 3. Scanning Electron Microscopy (SEM) micrograph of the polished surface and chemically attacked with hydrofluoric acid corresponding to the sample of Example 1.
FIG. 4. Micrografía de SEM de la superficie pulida y atacada químicamente correspondiente a la muestra del ejemplo 1 . Detalle de las fases cristalinas submicrónicas. FIG. 4. SEM micrograph of the polished and chemically attacked surface corresponding to the sample of example 1. Detail of the submicron crystalline phases.
EJEMPLOS EXAMPLES
Ejemplo 1. Formulación y procedimiento de obtención de un azulejo de gres porcelánico con propiedades mecánicas reforzadas. Example 1. Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
Se empleó la siguiente formulación de materias primas en porcentajes en peso respecto al peso total: The following formulation of raw materials was used in percentages by weight with respect to the total weight:
- 25% de caolinita (arcilla)  - 25% kaolinite (clay)
- 22% de illita (arcilla)  - 22% illite (clay)
- 31 % de dunita (silicato de hierro y magnesio) - 20% de cuarzo (arena) - 31% dunite (magnesium iron silicate) - 20% quartz (sand)
- 2% de feldespato.  - 2% feldspar.
La composición expresada en porcentaje en óxido equivalente respecto al total es: The composition expressed as a percentage in oxide equivalent to the total is:
- 55% de equivalente Si02 - 55% equivalent Si0 2
- 15% de equivalente AI2O3 - 15% equivalent AI2O3
- 13% de equivalente MgO - 13% MgO equivalent
- 5% de equivalente Fe2Ü3 - 5% equivalent Fe 2 Ü3
- 1 ,9% de equivalente K20 y - 1, 9% of equivalent K 2 0 and
- 8% equivalente pérdidas por calcinación como por ejemplo agua y carbonatos.  - 8% equivalent calcination losses such as water and carbonates.
- 2,1 % de equivalente de otros componentes minoritarios, Ti02, CaO, BaO, P205 y Na20 en una concentración menor al 1 % cada uno. - 2.1% equivalent of other minor components, Ti0 2 , CaO, BaO, P 2 0 5 and Na 2 0 in a concentration of less than 1% each.
La formulación anterior se homogeneizó en medio acuoso en una concentración del 60% en peso de contenido en sólidos. A dicha mezcla se añadió 0,2% en peso de un dispersante tipo tripolifosfato sódico y 0,05% en peso de un agente conservante tipo Adicide. La mezcla se homogeneizó mediante molienda en molino de bolas de alúmina para constituir una suspensión estable. La molienda realizada permite tener una mezcla de materias primas con un tamaño tal que el residuo de la barbotina al pasar por un tamiz de 63 μιη sea inferior al 3% en peso. Esta suspensión se secó por atomización para obtener un aglomerado con una distribución de tamaños entre 100-600 μιη. La humedad residual de los aglomerados atomizados se encontraba en un intervalo de 4-7% en peso. Los aglomerados se conformaron en un azulejo mediante el empleo de una prensa uniaxial que utilizó una presión de prensado de 250 kg/cm2. Los azulejos prensados en verde fueron secados en una estufa para la eliminación de la humedad correspondiente. El azulejo seco se trató térmicamente a una temperatura de 1 140°C en atmósfera oxidante en un horno monostrato de cocción rápida en un ciclo de 50 minutos de duración. El tiempo de mantenimiento a la máxima temperatura fue de 6 minutos. Como resultado se obtuvo un soporte de gres porcelánico con las siguientes propiedades físicas: The above formulation was homogenized in aqueous medium at a concentration of 60% by weight solids content. To this mixture was added 0.2% by weight of a sodium tripolyphosphate type dispersant and 0.05% by weight of an Additive type preservative. The mixture was homogenized by milling in alumina ball mill to constitute a stable suspension. The grinding carried out allows a mixture of raw materials with a size such that the slippery residue when passing through a sieve of 63 μιη is less than 3% by weight. This suspension was spray dried to obtain an agglomerate with a size distribution between 100-600 μιη. The residual moisture of the atomized agglomerates was in a range of 4-7% by weight. The agglomerates were formed in a tile by using a uniaxial press that used a pressing pressure of 250 kg / cm 2 . The pressed green tiles were dried in an oven to remove the corresponding humidity. The dried tile was heat treated at a temperature of 1 140 ° C in an oxidizing atmosphere in a fast-cooking monostrate oven in a 50-minute cycle. Maintenance time at maximum temperature was 6 minutes As a result, a porcelain stoneware support with the following physical properties was obtained:
Figure imgf000019_0001
Figure imgf000019_0001
El gres porcelánico está asimismo caracterizado por presentar las siguientes fases cristalinas identificadas por Difracción de Rayos X (XRD) (Fig. 1 ): Porcelain stoneware is also characterized by presenting the following crystalline phases identified by X-ray Diffraction (XRD) (Fig. 1):
Fases procedentes de las materias primas: Phases from raw materials:
- partículas cristalinas de cuarzo, Si02 con International Centre Difracción Data Number (ICDD No.) 019-1045, - crystalline quartz particles, Si0 2 with International Center Diffraction Data Number (ICDD No.) 019-1045,
Fases formadas durante el proceso de sinterización: Phases formed during the sintering process:
- Esteatita, MgSi03 ICDD No. 019-0768, - Soapstone, MgSi0 3 ICDD No. 019-0768,
- Forsterita, Mg2Si04 ICDD No. 034-0189, - Forsterite, Mg 2 Si0 4 ICDD No. 034-0189,
- Mullita, 2AI203.S¡02 ICDD No.074-2419 - Mullita, 2AI 2 0 3 .S¡0 2 ICDD No.074-2419
- Hercinita, FeAI204 ICDD No. 034-0192 - Hercinita, FeAI 2 0 4 ICDD No. 034-0192
Estas partículas están caracterizadas por presentar un tamaño de grano inferior a 500 nm y estar dispersas en la matriz vitrea para formar la microestructura del gres porcelánico reforzada por la presencia de fases cristalinas submicrónicas. Estas estructuras se pueden apreciar en las figuras 3 y 4. These particles are characterized by having a grain size of less than 500 nm and being dispersed in the vitreous matrix to form the microstructure of the porcelain stoneware reinforced by the presence of submicron crystalline phases. These structures can be seen in figures 3 and 4.
Ejemplo 2. Formulación y procedimiento de obtención de un azulejo de gres porcelánico con propiedades mecánicas reforzadas. Se empleó la misma formulación que en el ejemplo 1 y el mismo secado y conformado. Sin embargo, el azulejo seco se trató térmicamente a una temperatura de 1 160°C en atmósfera oxidante en un horno monoestrato de cocción rápida en un ciclo de 50 minutos de duración. El tiempo de mantenimiento a la máxima temperatura fue de 6 minutos. Como resultado se obtuvo un soporte de gres porcelánico con las siguientes propiedades físicas: Example 2. Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties. The same formulation as in example 1 and the same drying and forming was used. However, the dry tile was heat treated at a temperature of 1,160 ° C in an oxidizing atmosphere in a fast-firing monolayer oven in a 50-minute cycle. The maintenance time at maximum temperature was 6 minutes. As a result, a porcelain stoneware support with the following physical properties was obtained:
Figure imgf000020_0001
Figure imgf000020_0001
Por XRD se detectan las mismas fases cristalinas que las citadas en el ejemplo 1 . XRD detects the same crystalline phases as those mentioned in example 1.
Ejemplo 3. Formulación y procedimiento de obtención de un azulejo de gres porcelánico con propiedades mecánicas reforzadas. Example 3. Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
Se empleó la siguiente formulación de materias primas en porcentajes en peso respecto al total: The following formulation of raw materials in percentages by weight with respect to the total was used:
- 32% de caolinita (arcilla),  - 32% kaolinite (clay),
- 17% de illita (arcilla),  - 17% illite (clay),
- 33% de dunita (silicato de hierro y magnesio),  - 33% dunite (magnesium iron silicate),
- 15% de cuarzo (arena),  - 15% quartz (sand),
- 3% de feldespato.  - 3% feldspar.
La composición expresada en porcentaje en óxido equivalente respecto al total es: The composition expressed as a percentage in oxide equivalent to the total is:
- 53% de equivalente S1O2 - 53% equivalent S1O2
- 17,5% de equivalente AI2O3 - 12,5% de equivalente MgO - 17.5% AI2O3 equivalent - 12.5% MgO equivalent
- 4,2% de equivalente Fe203 - 4.2% equivalent Fe 2 0 3
- 1 ,5% de equivalente K20 y - 1.5% of equivalent K 2 0 and
- 9,7% equivalente pérdidas por calcinación como por ejemplo agua y carbonatos.  - 9.7% equivalent calcination losses such as water and carbonates.
- 1 ,6% de equivalente de otros componentes minoritarios, Ti02, CaO, BaO, Ρ2Οδ y Na20 en una concentración menor al 1 % cada uno. - 1, 6% equivalent of other minor components, Ti0 2 , CaO, BaO, Ρ 2 Ο δ and Na 2 0 in a concentration of less than 1% each.
El material de gres porcelánico se procesó siguiendo el procedimiento descrito en el ejemplo 1 (temperatura máxima 1 140°C). Como resultado se obtuvo un soporte de gres porcelánico con las siguientes propiedades físicas: The porcelain stoneware material was processed following the procedure described in example 1 (maximum temperature 1 140 ° C). As a result, a porcelain stoneware support with the following physical properties was obtained:
Figure imgf000021_0001
Figure imgf000021_0001
El gres porcelánico está asimismo caracterizado por presentar las siguientes fases cristalinas identificadas por Difracción de Rayos X (XRD) (Fig. 2): Porcelain stoneware is also characterized by presenting the following crystalline phases identified by X-ray Diffraction (XRD) (Fig. 2):
Fases procedentes de las materias primas: Phases from raw materials:
- partículas cristalinas de cuarzo, Si02 con International Centre Difracción Data Number (ICDD No.) 019-1045, - crystalline quartz particles, Si0 2 with International Center Diffraction Data Number (ICDD No.) 019-1045,
Fases formadas durante el proceso de sinterización: Phases formed during the sintering process:
- Esteatita, MgSi03 ICDD No. 019-0768, - Soapstone, MgSi0 3 ICDD No. 019-0768,
- Forsterita, Mg2Si04 ICDD No. 034-0189, - Forsterite, Mg 2 Si0 4 ICDD No. 034-0189,
- Mullita, 2AI203.S¡02 ICDD No. 074-2419 - Mullita, 2AI 2 0 3 .S¡0 2 ICDD No. 074-2419
- Hercinita, FeAI204 ICDD No. 034-0192 Estas partículas están caracterizadas por presentar un tamaño de grano inferior a 500 nm con un número importante de partículas cristalinas con tamaños inferiores a 200 nm. - Hercinita, FeAI 2 0 4 ICDD No. 034-0192 These particles are characterized by having a grain size of less than 500 nm with a significant number of crystalline particles with sizes less than 200 nm.
Ejemplo 4. Formulación y procedimiento de obtención de un azulejo de gres porcelánico con propiedades mecánicas reforzadas. Example 4. Formulation and procedure for obtaining a porcelain stoneware tile with reinforced mechanical properties.
Se empleó la siguiente formulación de materias primas en porcentajes en peso respecto al total: The following formulation of raw materials in percentages by weight with respect to the total was used:
- 22% de caolinita (arcilla),  - 22% kaolinite (clay),
- 16% de illita (arcilla), - 16% illite (clay),
- 25% de dunita (silicato de magnesio y hierro),  - 25% dunite (magnesium iron silicate),
- 16% de clorita (silicato de magnesio y hierro), - 16% chlorite (magnesium iron silicate),
- 20% de cuarzo (arena)  - 20% quartz (sand)
- 1 % de feldespato. - 1% feldspar.
La composición expresada en porcentaje en óxido equivalente respecto al total es: The composition expressed as a percentage in oxide equivalent to the total is:
- 53,5% de equivalente Si02 - 53.5% of equivalent Si0 2
- 17,5% de equivalente AI2O3 - 17.5% AI2O3 equivalent
- 12,5% de equivalente MgO - 12.5% MgO equivalent
- 4,5% de equivalente Fe2Ü3 - 4.5% equivalent Fe 2 Ü3
- 1 ,6% de equivalente K20 y - 1, 6% of equivalent K 2 0 and
- 8,7% equivalente pérdidas por calcinación como por ejemplo agua y carbonatos.  - 8.7% equivalent calcination losses such as water and carbonates.
- 2,7% de equivalente de otros componentes minoritarios, Ti02, CaO, BaO, P205 y Na20 en una concentración menor al 1 % cada uno. - 2.7% equivalent of other minor components, Ti0 2 , CaO, BaO, P 2 0 5 and Na 2 0 in a concentration of less than 1% each.
El material de gres porcelánico se procesó siguiendo el procedimiento descrito en el ejemplo 1 (temperatura máxima 1 140°C). Como resultado se obtuvo un soporte de gres porcelánico con las siguientes propiedades físicas: densidad 2,42 g/cm" The porcelain stoneware material was processed following the procedure described in example 1 (maximum temperature 1 140 ° C). As a result, a porcelain stoneware support with the following physical properties was obtained: density 2.42 g / cm "
coeficiente de dilatación térmica (50- 55x10"' °C"1 thermal expansion coefficient (50- 55x10 " '° C " 1
300°C) 300 ° C)
Módulo de resistencia mecánica a la 820 kg/cm  Mechanical resistance module at 820 kg / cm
flexión flexion
Coeficiente de restitución 0,82  Coefficient of restitution 0.82
El gres porcelánico está asimismo caracterizado por presentar las siguientes fases cristalinas identificadas por Difracción de Rayos X (XRD): Porcelain stoneware is also characterized by presenting the following crystalline phases identified by X-ray Diffraction (XRD):
Fases procedentes de las materias primas: Phases from raw materials:
- partículas cristalinas de cuarzo, Si02 con International Centre Difracción Data Number (ICDD No.) 019-1045, - crystalline quartz particles, Si0 2 with International Center Diffraction Data Number (ICDD No.) 019-1045,
Fases formadas durante el proceso de sinterización: Phases formed during the sintering process:
- Esteatita, MgSi03 ICDD No. 019-0768, - Soapstone, MgSi0 3 ICDD No. 019-0768,
- Forsterita, Mg2Si04 ICDD No. 034-0189, - Forsterite, Mg 2 Si0 4 ICDD No. 034-0189,
- Mullita, 2AI203.S¡02 ICDD No. 074-2419 - Mullita, 2AI 2 0 3 .S¡0 2 ICDD No. 074-2419
- Hercinita, FeAI204 ICDD No. 034-0192 - Hercinita, FeAI 2 0 4 ICDD No. 034-0192

Claims

R E I V I N D I C A C I O N E S
1 . - Gres porcelánico que comprende cristales de silicatos seleccionados de la lista que comprende silicatos de magnesio, silicatos de hierro y silicatos de magnesio y hierro, donde los cristales están homogéneamente distribuidos y tienen un tamaño medio de 20 nm a 1000 nm, preferiblemente de 50 a 500 nm. one . - Porcelain stoneware comprising silicate crystals selected from the list comprising magnesium silicates, iron silicates and magnesium and iron silicates, where the crystals are homogeneously distributed and have an average size of 20 nm to 1000 nm, preferably 50 to 500 nm
2. - El gres porcelánico según la reivindicación anterior donde los cristales de silicatos pertenecen al grupo mineral olivino. 2. - The porcelain stoneware according to the preceding claim wherein the silicate crystals belong to the olivine mineral group.
3. - El gres porcelánico según cualquiera de las reivindicaciones anteriores que además comprende cristales de cuarzo, donde los cristales de cuarzo tienen un tamaño medio de 0,5 μιη a 100 μιη, preferiblemente de 1 m a 40 μιη. 3. - The porcelain stoneware according to any of the preceding claims which further comprises quartz crystals, wherein the quartz crystals have an average size of 0.5 μιη to 100 μιη, preferably 1 m to 40 μιη.
4. - El gres porcelánico según cualquiera de las reivindicaciones anteriores que comprende cristales de indialita en una proporción menor al 10%, preferiblemente menor al 5%. 4. - The porcelain stoneware according to any of the preceding claims comprising indialite crystals in a proportion of less than 10%, preferably less than 5%.
5. - El gres porcelánico según cualquiera de las reivindicaciones anteriores donde la proporción de Mg, expresada en porcentaje en peso del óxido equivalente respecto al peso total es de 8% a 22%, preferiblemente de 10% a 20%. 5. - The porcelain stoneware according to any of the preceding claims wherein the proportion of Mg, expressed as a percentage by weight of the equivalent oxide with respect to the total weight is 8% to 22%, preferably 10% to 20%.
6. - El gres porcelánico según cualquiera de las reivindicaciones anteriores donde la proporción de Fe, expresada en porcentaje en peso del óxido equivalente respecto al peso total es de 2% a 15%, preferiblemente de 3% a 10%. 6. - The porcelain stoneware according to any of the preceding claims wherein the proportion of Fe, expressed as a percentage by weight of the equivalent oxide with respect to the total weight is from 2% to 15%, preferably from 3% to 10%.
7. - El gres porcelánico según cualquiera de las reivindicaciones anteriores que además comprende unas proporciones de un 40% a 70% de Si y un 5% a 22 % de Al, expresadas en porcentaje en peso del óxido equivalente respecto al total. 7. - The porcelain stoneware according to any of the preceding claims which further comprises proportions of 40% to 70% Si and 5% to 22% Al, expressed as a percentage by weight of the equivalent oxide with respect to the total.
8.- El gres porcelánico según cualquiera de las reivindicaciones anteriores que además comprende Na, K y Ca en proporciones inferiores a 5% expresadas en porcentaje en peso de los respectivos óxidos equivalente respecto al peso total. 8. The porcelain stoneware according to any of the preceding claims which further comprises Na, K and Ca in proportions less than 5% expressed as a percentage by weight of the respective equivalent oxides with respect to the total weight.
9. - El gres porcelánico según cualquiera de las reivindicaciones anteriores que además comprende otros compuestos minoritarios en una proporción inferior al 1 % en peso respecto del total de la composición. 9. - The porcelain stoneware according to any of the preceding claims which further comprises other minor compounds in a proportion less than 1% by weight with respect to the total composition.
10. - El gres porcelánico según cualquiera de las reivindicaciones anteriores, donde la densidad es de al menos 2,4 g/cm3. 10. - The porcelain stoneware according to any of the preceding claims, wherein the density is at least 2.4 g / cm 3 .
1 1 . - El gres porcelánico según cualquiera de las reivindicaciones anteriores que además comprende una capa de engobe. eleven . - The porcelain stoneware according to any of the preceding claims which further comprises a slip layer.
12. - El gres porcelánico según cualquiera de las reivindicaciones anteriores que además comprende una capa de esmalte. 12. - The porcelain stoneware according to any of the preceding claims which further comprises an enamel layer.
13. - Procedimiento de obtención del gres porcelánico según cualquiera de las reivindicaciones anteriores que comprende las etapas de: a) mezclado en medio acuoso de: i) al menos una arcilla plástica en una proporción de 40% a 70% en peso, 13. - Method of obtaining the porcelain stoneware according to any of the preceding claims comprising the steps of: a) mixing in aqueous medium of: i) at least one plastic clay in a proportion of 40% to 70% by weight,
ii) al menos un mineral de hierro, magnesio o ambos en una proporción de 10% a 40% en peso,  ii) at least one iron ore, magnesium or both in a proportion of 10% to 40% by weight,
iii) al menos una arena en una proporción de 5% a 30% en peso, y iv) al menos un feldespato en una proporción de 0,5% a 10% en peso. b) secado del producto obtenido en la etapa anterior c) conformado de piezas del producto obtenido en la etapa anterior d) cocer la mezcla resultante de la etapa anterior iii) at least one sand in a proportion of 5% to 30% by weight, and iv) at least one feldspar in a proportion of 0.5% to 10% by weight. b) drying of the product obtained in the previous stage c) forming parts of the product obtained in the previous stage d) cook the mixture resulting from the previous stage
14. - El procedimiento de obtención según la reivindicación anterior donde la arcilla plástica comprende filosilicatos. 14. - The method of obtaining according to the preceding claim wherein the plastic clay comprises phyllosilicates.
15. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 14, donde la arena comprende partículas cristalinas de cuarzo 15. - The method of obtaining according to any of claims 13 to 14, wherein the sand comprises crystalline quartz particles
16. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 15, donde el feldespato comprende un grupo de minerales tectosilicatos que se encuentran constituidos fundamentalmente por rocas de tipo ígneo. 16. - The method of obtaining according to any of claims 13 to 15, wherein the feldspar comprises a group of tectosilicate minerals that are constituted mainly of igneous type rocks.
17. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 16, donde el mineral de hierro, magnesio o ambos es un nesosilicato, preferiblemente del grupo olivino. 17. - The method of obtaining according to any of claims 13 to 16, wherein the iron ore, magnesium or both is a nesosilicate, preferably of the olivine group.
18. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 17 donde la proporción de Mg, expresada en porcentaje en peso del óxido equivalente respecto al peso total es de 8% a 22%, preferiblemente de 10% a 20%. 18. - The method of obtaining according to any one of claims 13 to 17 wherein the proportion of Mg, expressed as a percentage by weight of the equivalent oxide with respect to the total weight is 8% to 22%, preferably 10% to 20%.
19. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 18 donde la proporción de Fe, expresada en porcentaje en peso del óxido equivalente respecto al peso total es de 2% a 15%, preferiblemente de 3% a 10%. 19. - The method of obtaining according to any one of claims 13 to 18 wherein the proportion of Fe, expressed as a percentage by weight of the equivalent oxide with respect to the total weight is from 2% to 15%, preferably from 3% to 10%.
20. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 19 donde las proporciones de un 40% a 70% de Si y un 5% a 22 % de Al, expresadas en porcentaje en peso del óxido equivalente respecto al total. 20. - The method of obtaining according to any of claims 13 to 19 wherein the proportions of 40% to 70% Si and 5% to 22% Al, expressed as a percentage by weight of the equivalent oxide with respect to the total.
21 . - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 20 donde las proporciones de Na, K y Ca expresadas en porcentaje en peso de los respectivos óxidos equivalente respecto al peso total inferiores a 5%. twenty-one . - The method of obtaining according to any of claims 13 to 20 wherein the proportions of Na, K and Ca expressed in weight percent of the respective oxides equivalent to the total weight of less than 5%.
22. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 21 , que comprende una etapa (a1 ) posterior a (a) y anterior a (b) de adición de al menos un aditivo, donde el aditivo se selecciona de la lista que comprende defloculates, dispersantes, antiespumantes, y bactericidas. 22. - The method of obtaining according to any one of claims 13 to 21, comprising a step (a1) after (a) and before (b) adding at least one additive, wherein the additive is selected from the list comprising defloculates, dispersants, antifoams, and bactericides.
23. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 22, que comprende una etapa (a2) anterior a (b) de homogeneización por molienda o dispersión del producto obtenido en la etapa anterior. 23. - The method of obtaining according to any of claims 13 to 22, comprising a step (a2) prior to (b) homogenization by grinding or dispersion of the product obtained in the previous stage.
24. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 23 donde el secado se lleva a cabo por atomizado. 24. - The method of obtaining according to any of claims 13 to 23 wherein the drying is carried out by spraying.
25. - El procedimiento de obtención según cualquiera de las reivindicaciones anteriores donde la etapa de conformado de piezas se lleva a cabo por prensado uniaxial, prensado isostático, o extrudido de cuerpos cerámicos en verde. 25. - The method of obtaining according to any of the preceding claims wherein the step of forming parts is carried out by uniaxial pressing, isostatic pressing, or extrusion of ceramic bodies in green.
26. - El procedimiento de obtención según la reivindicación anterior que comprende una etapa (c1 ) posterior a (c) y anterior a (d) de aplicación del engobe. 26. - The method of obtaining according to the preceding claim comprising a step (c1) after (c) and before (d) application of the engobe.
27. El procedimiento de obtención según cualquiera de las reivindicaciones de 25 a 26 que comprende una etapa (c2) anterior a (d) de esmaltado del producto resultante de la etapa anterior. 27. The method of obtaining according to any of claims 25 to 26 comprising a step (c2) prior to (d) enamelling the product resulting from the previous stage.
28. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 27 donde la cocción de la etapa (d) se lleva a cabo en ciclo industrial, preferentemente en monococción en un horno monoestrato de gas de cocción rápida. 28. - The method of obtaining according to any one of claims 13 to 27 wherein the cooking of step (d) is carried out in an industrial cycle, preferably in monocoction in a fast-cooking gas monostrat oven.
29. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 28, donde la temperatura de la cocción de la etapa (d) está comprendida entre 980°C y 1280°C, preferiblemente entre 1 100°C y 1200°C 29. - The method of obtaining according to any of the claims of 13 to 28, where the cooking temperature of stage (d) is between 980 ° C and 1280 ° C, preferably between 1 100 ° C and 1200 ° C
30. - El procedimiento de obtención según cualquiera de las reivindicaciones de 13 a 29, donde la cocción de la etapa (d) comprende ciclos rápidos de sinterización con tiempos de residencia a la máxima temperatura de los ciclos entre 1 y 30 minutos, preferente entre 2 y 20 minutos. 30. - The method of obtaining according to any of claims 13 to 29, wherein the cooking of step (d) comprises rapid sintering cycles with residence times at the maximum temperature of the cycles between 1 and 30 minutes, preferably between 2 and 20 minutes.
31 . - El uso del gres porcelánico según las reivindicaciones de 1 a 12 como pieza de recubrimiento o decorativa en suelos, paredes, fachadas, mobiliario, sanitarios. 31. - The use of porcelain stoneware according to claims 1 to 12 as a covering or decorative piece in floors, walls, facades, furniture, sanitary ware.
32. - El uso según la reivindicación anterior donde la pieza es de gran formato. 32. - The use according to the preceding claim where the piece is large format.
PCT/ES2013/070667 2012-09-25 2013-09-25 Composition and method for producing reinforced ceramic tiles made from porcelain stoneware WO2014049189A1 (en)

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CN110678432A (en) * 2017-05-05 2020-01-10 活性矿物国际有限公司 Composition for completely or partially replacing ball clay in ceramic and preparation method and application thereof
KR20200005556A (en) * 2017-05-05 2020-01-15 엑티브 미네랄스 인터내셔널 엘엘씨 COMPOSITION TO COMPLETELY OR PARTIALLY REPLACE BALL CLAY IN CERAMICS, METHOD OF MAKING, AND USE THEREOF
EP3619181A4 (en) * 2017-05-05 2021-01-20 Active Minerals International, LLC Composition to completely or partially replace ball clay in ceramics, method of making, and use thereof
US11198646B2 (en) 2017-05-05 2021-12-14 Active Minerals International, Llc Composition to completely or partially replace ball clay in ceramics, method of making, and use thereof
CN110678432B (en) * 2017-05-05 2022-06-07 活性矿物国际有限公司 Composition for completely or partially replacing ball clay in ceramic and preparation method and application thereof
US11708307B2 (en) 2017-05-05 2023-07-25 Active Minerals International, Llc Composition to completely or partially replace ball clay in ceramics, method of making, and use thereof
KR102616059B1 (en) 2017-05-05 2023-12-19 엑티브 미네랄스 인터내셔널 엘엘씨 COMPOSITION TO COMPLETELY OR PARTIALLY REPLACE BALL CLAY IN CERAMICS, METHOD OF MAKING, AND USE THEREOF

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