An engineered stone composition, a decorative element made of an engineered stone and a method for manufacturing an engineered stone

Abstract

A composition for manufacturing an engineered stone, said composition comprising a binder and a mineral filler, wherein said binder represents less than 15 % on a weight basis of the composition wherein: - said mineral filler comprises one or more feldspathoid; and / or - said mineral filler comprises a feldspar.

Description

[0001] An engineered stone composition, a decorative element made of an engineered stone and a method for manufacturing an engineered stone.

[0002] The present invention relates to a composition for manufacturing an engineered stone. The invention further relates to a decorative element, for example a decorative slab like a kitchen top, made of an engineered stone. In particular, the engineered stone of the invention is often known on the market as quartz. The invention further relates to a method for manufacturing an engineered stone.

[0003] An engineered stone comprises an mineral filler like crushed stones, sands or other minerals but also recycled ceramic or glass, bonded by means of a cured polymeric binder. More in detail, with engineered stone is intended a composite material formed by an mineral filler or a stone like material bonded together by means of a cured polymeric binder that it is cured at low temperature, wherein with low temperature is intended a temperature below 500°C. The binder is preferably a thermosetting resin.

[0004] Traditionally, natural stone is used as building material, especially for finishing building surfaces like for example for coverings of wall or floor and for producing worktops like kitchen or bathroom countertops and vanities. Natural stones are extracted from mines and subsequently cut and polished to obtain slabs or boards of the desired shape. Due to the mine extraction, natural stones are relatively expensive and produce a high impact on the environment.

[0005] Therefore, in the past years methods for manufacturing engineered stones were developed in order to reduce costs and provide a more environmentally friendly product. A well-known example of such methods is represented by the so called Bretonstone® technology described, for example, in the document, WO 2007 / 138529. Said document discloses a method for manufacturing an engineered stone which comprises the step of: providing a mineral filler, for example by sand or quartz; mixing the stone or stone like material with a binder, for example a resin powder, in order to obtain a mixture; depositing the mixture in a mold of a press, having shape and dimension similar to those of the final article; press the mixture applying vacuum, with the accompanying application of a vibratory motion at pre-established frequency; the semi-product obtained is then hardened by means of a heat curing process to obtain the engineered stone; the engineered stone is then subjected to finishing steps like cutting or polishing.

[0006] Mineral filler used in engineered stone is normally mainly composed or more or less pure silicon oxide (silica), in particular in its quartz or cristobalite form. Quartz and cristobalite are different form of silicon oxide which are preferred above other for their hardness, chemical durability and transparency. Both quartz and cristobalite are crystalline. Crystalline silica when inhaled, for example in the form of fine powder coming from cutting of the material, can cause a lung disease known as silicosis. For this reason, several attempts have been made to find alternative fillers that can substitute crystalline silica. In particular, US 2022 / 0089485 proposes use of tow specific formulation of feldspar for substituting a fraction of the quartz or cristobalite filler, the remaining being substituted by other minerals like calcium carbonate, synthetic granules, for example glass or ceramics. US 11,753,336 proposes a specific glass composition to substitute quartz and cristobalite.

[0007] The present invention aims in the first place to provide an alternative composition for an engineered stone, which, in accordance with several of its preferred embodiments, is directed to solving one or more of the problems arising in the state of the art.

[0008] Thereto, the present invention, according to its first independent aspect, relates to a composition for manufacturing an engineered stone, said composition comprising a binder and a mineral filler, wherein said binder represents less than 15 % on a weight basis of the composition. With the characteristics that said composition of the first aspect can comprise one or more of the main properties listed below which, either alone or in combination each other, can provide effects directed to solve some of the problems of the prior art.

[0009] In accordance with a first main property, said mineral filler can comprise one or more feldspathoid. The term feldspathoid identifies a group of minerals formed by igneous generation and that comprise a composition similar, but different, to that of feldspars and often with a lower content of free crystalline silica. Inventors have found that feldspathoids can show a content of free crystalline silica being null or very close to zero. Preferably, feldspathoid in accordance with said first possibility can show a content of free crystalline silica below 5% of the weight of the feldspathoid, more preferably below 3% of the weight of the feldspathoid. In this way feldspathoids can represent an interesting alternative to synthetic amorphous granules, like glass and ceramics.

[0010] In the context of the present invention, feldspathoid can comprise general formula ZAlSixOy where: Z can be selected from the group comprising K, Na, Ca, Li; X can assume any integer value between 1 to 6; and Y can assume value 4, 6, or 10. Feldspathoid can be selected from the group comprising, preferably consisting of: leucite (KAlSi2Oe), nepheline ((Na,K)AlSiO4), petalite (LiAlSi40io), kalsilite (KAlSiCU). Preferably, said feldspathoid in the composition mainly comprises or consists of nepheline. With mainly comprises it is meant that at least 50% based on the total weight of feldspathoid in the composition is formed by nepheline. Nepheline, that has general formula (Na,K)AlSiO4, is transparent or translucent, hard and durable and can be totally free from free crystalline silica. In particular, inventors have found that nepheline can be used to substitute cristobalite in the composition of a determined product thereby limiting the color change expressed as AE CIELAB (measured in accordance to ISO 12647- 2:2013) below 5, even more preferably below 3.

[0011] Nepheline can comprise the following general composition expressed in percentage by weight: SiO258 - 62 %; A12O320 - 25 %; Na2O 8 - 12 %; K2O 2 - 6%; CaO 0 - 2 %; MgO 0 - 1 %.

[0012] In the preferred embodiment of this first property, said feldspathoid can represent 50% or more, possibly 60% or more, even more preferably 70% or more of the weight of the mineral filler. The feldspathoid can represent 100% or less of the weight of the mineral filler, preferably 90% or less, possibly 80% or less of the weight of the mineral filler. In this way the content of filler poor in free crystalline silica can be maximized while the color of obtained engineered stone not affected. In particular, the inventors have found that in this way, especially when nepheline is used, feldspathoid can substitute cristobalite in the composition of a determined product thereby limiting the color change expressed as AE CIELAB (measured in accordance to ISO 12647-2:2013) below 3. On the other hand setting an upper limit to the content of the feldspathoid in the mineral filler can help limiting the content of free crystalline silica in the composition while limiting the color shift when converting a certain product from a cristobalite or silica based composition to a new composition with lower free crystalline silica.

[0013] Preferably said feldspathoid can represent at least 70% of the total weight of the composition, preferably at least 80% of the composition. By maximizing the content of feldspathoid in the composition and compared to other mineral fillers it is possible to minimize, and possibly avoid, the presence of crystalline silica in the engineered stone. Therefore, nepheline can represent a good candidate for substituting quartz and cristobalite engineered stone, especially in the white ones.

[0014] In accordance with a second main property, said mineral filler can comprise a feldspar. Feldspars are silicate mineral having general formula M(AlSi)40s, where M is selected from the group comprising: K, Na, B, Ca Rb, Sr, Fr. In particular it is preferred that in said feldspar Na and / or K are predominant above Ca. Preferably, said feldspar comprises the following composition: SiCh 68 - 72 %; AI2O3 16 - 20 %; Na2O 6 - 10 %; K2O 1 - 5%; CaO 0 - 2 %. Inventors have found that feldspar having said composition can show a reduced amount of crystalline silica, so that the said feldspar can be extensively used in the composition thereby providing engineered stone with a residual free crystalline silica content below 5% based on the total weight of the engineered stone. Sodium aor potassium based feldspar tend to show a pure white, possibly transparent, color that render them particularly interesting when used in engineered stone composition for decorative elements.

[0015] In the preferred embodiment of this first property, said feldspar can represent 10% or more, possibly 20% or more, even more preferably 30% or more of the weight of the mineral filler. The feldspar can represent 80% or less of the weight of the mineral filler, preferably 70% or less possibly 60% or less. In accordance with a third main property of the first aspect of the invention, the composition can comprise both a feldspar and a feldspathoid as described with reference to the first and second main property. In this case, it is preferable that the feldspathoid be predominantly over the feldspar in the composition. In this way it may be possible that the residual amount of crystalline silica in the engineered stone is further reduced whereas the color thereof is closer to that of a composition based on quartz and / or cristobalite. In particular, it is preferred that the feldspathoid and the feldspar are present in the composition in a ratio between 1,5: 1 and 9: 1, more preferably in a ratio between 2: 1 and 4: 1. In this way, feldspathoid can help limiting the quantity of free crystalline silica in the composition, while the presence of feldspar, and in particular of sodium based feldspar, can help limiting color shift when changing the composition of a determined product from a silica or cristobalite based composition. Preferably, the sum of the amount of said feldspathoid and said feldspar represent the between 95 and 100% of the mineral filler

[0016] In this third main property, it is preferable that the feldspathoid represents from 50 to 90% of the weight of the mineral filler in the composition.

[0017] It is preferable that, in this third main property, feldspathoid represents from 50 to 90% of the weight of the mineral filler in the composition.

[0018] In accordance with any of the abovementioned main properties, the mineral filler can further comprise synthetic minerals like ceramics, glass and / or mirrors, and / or can comprise other non-silicate minerals, like for example calcium carbonate.

[0019] In accordance with any of the abovementioned main properties, the amount of free crystalline silica in the composition is less than 5% on a weight basis of the composition, preferably below 2%.

[0020] In accordance with any of the abovementioned main properties, the mineral filler can be provided in form of grits and in form of powder, wherein with grits it is referred to particulates or granules having a maximum diameter above 0, 1 mm and wherein with powders it is referred to granules or particulates having maximum diameter below 0,1 mm. Preferably, said grit represents more than the 50 % based on the total weight of the composition, for example between 55 and 65. Preferably, said powder represents more than the 15 % based on the total weight of the composition, for example between 20 and 30 %. Preferably, said grit represents more than 60 % based on the total weight of the mineral filler, for example between 65 and 75 %. Preferably, said powder represents more than 20 % based on the total weight of the composition, for example between 25 and 35 %.

[0021] In accordance with any of the abovementioned main properties, grit can be formed by a plurality of groups of particles having different dimensions. For example, a first group can comprise particles with a maximum dimension comprised between 0,1 and 0,3 mm; a second group can comprise particles with a maximum dimension comprised between 0,3 and 0,7 mm; a third group can comprise particles with a maximum dimension comprised between 0,7 and 1,2 mm; a fourth group can comprise particles with a maximum dimension comprised between 1,2 and 2,5 mm.

[0022] Preferably said feldspathoid and / or feldspar of the first, second and third main properties can be comprised in both the above-mentioned powder and said abovementioned grit, or in only one of them. Preferably, said feldspathoid and / or feldspar of the first, second and third main properties can be comprised in any of the first, second and third groups of said grit. Preferably, said synthetic mineral filler can be comprised in said fourth group of said grit.

[0023] The binder can be a polymeric binder, more preferably a thermosetting binder. In the preferred embodiment of the invention, said binder can be a polyester resin, more in particular an unsaturated polyester resin. The composition can comprise an amount of binder above 5 % based on the total weight of the composition, for example said amount is comprised between 8 and 12 % of the composition. The composition, in accordance with any of its embodiments or properties, can further comprise additives, in an amount below 5% of the total weight of the composition. The composition can comprise one or more of the additives included in the group consisting of: crosslinker, for example styrene monomer; and / or catalyst, for example cobalt-based catalyst; and / or initiator, for example organic peroxide; and / or coupling agent, for example silane-based coupling agent.

[0024] Said additives can be premixed in the binder and their and their amount being included in the amount of binder mentioned above.

[0025] The composition can comprise one or more pigments. Said pigments can be in liquid or powder form. Said pigments can be organic or inorganic, although inorganic binders are preferred in view of their higher durability. In case the composition is for manufacturing a white slab, the pigment is preferably titanium dioxide. In this case the pigment can be present in the composition in an amount of at least 1,5 %, preferably at least 2 % based on the total weight of the composition.

[0026] In its second independent aspect the invention relates to a method for manufacturing a decorative element made of an engineered stone wherein said method comprises the steps of: providing a composition comprising at least a binder and a mineral filler on a carrier, preferably a mold; compacting said composition on said carrier, preferably by means of vibration and / or vacuum; curing said binder, preferably by means of heating. The composition can comprise one or more of the features described above in relation to the first independent aspect.

[0027] In the method of the second independent aspect, the step of providing the composition can comprise the step of mixing the components of the composition, i.e mineral filler, resin, additives and / or pigments, in order to obtain a mixture. At the end of this mixing step the composition is in a solid and wet form. In other words, the composition is in the form of a particulate mass where the particles of the mass (for example grit and powder of the mineral filler) are wet by liquid or fluid components, like the binder. The composition is provided into a mold, preferably made of rubber. The mold can be formed by a container body and a vessel. In alternative embodiments, the mold can be substituted by a support like a paper sheet.

[0028] It is possible that the method comprises the step of pre-compacting said composition before it is provided on the carrier. For example, the composition, after being mixed, can be pre-compacted by passing through one or more couples of opposite compacting rollers. In this way it is possible to obtain a belt of composition where a part of the air and void between particles of the composition is removed before the compacting step. This operation is of particular interest when the engineered stone is manufactured in the form of a slab and has the advantage that a limited amount of material is necessary to make the final product, because it can lead to a limited need for flattening or thickening operations after the curing step to obtain a well flat slab with the desired thickness. An important side effect of this operation is that by limiting the need for machining steps like flattening and thickening, the amount of dust released in the factory, included any possible free crystalline silica, can be further reduced.

[0029] Preferably the compacting step is conducted under vacuum, i.e. vacuum is generated in the mold to help extracting air between the composition particles. More preferably, vibration is applied to the mold or frame during the compacting step thereby helping to compact the composition particles, so that the porosity of the engineered stone is significantly reduced. According to a preferred embodiment both vacuum and vibration are applied to the composition during the compression. In this way, it is possible to obtain a very high degree of compaction of the composition that after curing will lead to an extremely low porosity.

[0030] After the compacting step, the composition in the mold is carried to a curing station. In the preferred embodiment, the curing step is conducted at a temperature below 500°C, for example below 200°C, for example at room temperature. In particular, in the preferred example the curing step can be thermally activated and continues in an exothermic reaction. The activation of the curing of the binder can occur at a temperature below 100°C.

[0031] Optionally, the method can comprise one or more machining steps of the decorative material after said step of curing. Said machining steps can comprise one or more of the machining operations belonging to the group comprising, preferably consisting of: flattening, thickening, polishing and / or squaring.

[0032] Optionally, the method can comprise one or more decorative steps for forming a decorative pattern in said decorative element. Said decorative pattern can be made according to several possibility, three of them are described hereinbelow, that can be performed either singularly or in combination each other.

[0033] In a first of said possibilities, the decorative pattern, or at least a portion thereof, can be performed by spreading a second composition, having a color different from said first composition, on the carrier, wherein said second composition is spread randomly or according to a determined pattern. This first possibility is performed before the compacting step.

[0034] In a second of said possibilities, the decorative pattern, or at least a portion thereof, can be performed by creating cavities in the mass of first composition on said carrier and filling said cavities with a second composition, having a color different from said first composition. In this case, said cavities are formed according to a predetermined pattern. This second possibility is performed before the compacting step.

[0035] In a third of said possibilities, the decorative pattern, or at least a portion thereof, can be performed by jetting one or more inks on at least one surface of said decorative element. This third possibility is performed after the curing step.

[0036] In accordance with its third independent aspect, the invention can relate to a decorative element made of an engineered stone wherein said engineered stone comprises the composition according to the first independent aspect and / or obtained by the method of the second independent aspect. The decorative element of the third independent aspect can preferably be in form of a slab or board. The decorative element of the third independent aspect can be used, for example, as a furniture cladding, like kitchen or bathroom top, wall covering or floor covering.

[0037] With the intention of better showing the characteristics of the invention, in the following, as an example without any limitative character, several preferred embodiments are described with reference to the accompanying drawings, wherein:

[0038] Figure l is a perspective view of an engineered stone in accordance with the invention; Figure 2 shows some steps in a method for manufacturing the engineered stone of Figure 1.

[0039] Figure 1 shows an engineered stone 1 which is in the form of a slab and has a length X of at least 2 m, preferably at least 2.5 m, most preferably at least 3 m, and a width Y of at least 1 m preferably at least 1.5 m, most preferably at least 1.9 m. Moreover, the engineered stone 1 shows a thickness Z of at least 10 mm, preferably at least 20 mm for example 30 mm.

[0040] The engineered stone 1 is made of a composition that comprises an mineral filler and a cured binder that bonds together the particles of mineral filler. The filler is composed of a combination of powder and grits, for example said combination comprises at least 60 wt% of grits and between 20 to 35 wt% of powder wherein, for example, the gritshave a particles size distribution between 0.1 and 6.5 mm and the powder have an average particle dimension lower than 45 pm, preferably lower than 20 pm. The filler is preferably at least the 80% by weight of the mixture, preferably more than the 85% and more preferably more than 90%.

[0041] In the example the mineral filler is entirely formed by a combination of feldspar and feldspathoid wherein the feldspar forms 20% of the weight of the composition and the feldspathoid forms 80% of the weight of the mineral filler. In the example the feldspathoid is nepheline comprising an amount of free crystalline silica below 1% of the weight of the feldspathoid and that comprises the composition indicated in table 1.

[0042] In the example the feldspar is sodium or potassium based, for example albite, comprising an amount of free crystalline silica below 5% of the weight of the feldspar and that comprises the composition indicated in table 2.

[0043] The binder is a resin comprising an unsaturated polyester, a cross-linker and at least one initiator. It is possible to further add an accelerator, for example 5 wt% of Cobalt accelerator. The composition preferably further also comprises a silane adhesion promotor.

[0044] The binder is in powder form and forms up to 10% by weight of the total weight of the composition. The engineered stone 1 comprises a first decorative pattern 2. The first decorative pattern 2 is a three-dimensional decoration that is present in the entire thickness of the engineered stone 1.

[0045] Figure 2 shows some steps in a method, according to the invention, for manufacturing the engineered stone 1 of figure 1.

[0046] In a step SI a composition 10 is provided into a mold 15 for manufacturing the engineered stone 1. The composition 10, in the form of a particulate.

[0047] In step SI the mixture 10 is deposited from a hopper 11 on a first belt 12. A feeder 13 feeds a first set of coloring agents 14 to the mixture 10 on the first belt 12. By virtue of the advancing of the first belt 12, the mixture 10 with the first coloring agents 14 falls into a mold 15 disposed on a second belt 16 placed below the first belt 12. As a consequence of this fall, the first coloring agent 14 is randomly distributed into the mixture 10 in the mold 15.

[0048] Once the mixture 10 is in the mold 15, a robotic arm 17 delivers a second set of coloring agents 18 into the mixture 10 according to a predetermined motif. The motif obtained by the combination of the first set of coloring agents 14 and the second set of coloring agents 18 substantially forms the first decorative pattern 2.

[0049] The composition 10 in the mold 15 advances in an advancing direction A to a compacting station 19 for a compaction step S2. Said compacting station 19 comprises a vibrating unit 20 and a vacuum unit 21, for the application of vibration and vacuum on the mixture in the mold 15 that leads to the compaction thereof.

[0050] The composition 10, yet in the mold, is then carried to a curing station 22 where the binder is cured in a curing step S3. The cure of the binder is activated at a temperature below 200 °C, for example 120 °C, and then continues as an exothermic reaction. After the curing step S3, the obtained engineered stone 1, which is now a coherent material having a porosity below 0.2%, is then extracted from the mold 15 and carried to multiple mechanical machining station for finishing operations.

[0051] In a step S4, the engineered stone 1 is subjected to a flattening and / or thickening operation to flatten at least the upper surface thereof and or to achieve the desired thickness Z. Subsequently in a step S5, the engineered stone 1 is rectified so that it finally reaches the desired final shape and dimension.

[0052] Subsequently, at least the upper surface of the engineered stone 1 is mechanically treated in a polishing step S6, to provide the final surface finish. The engineered stone 1 is ready and may be used as is or for further applications, such as for forming a decorative element like a kitchen countertop.

[0053] The present invention is in no way limited to the hereinabove described embodiments, but such engineered stone and method for manufacturing thereof may be realized according to different variants without leaving the scope of the present invention.

[0054] Further, as is clear from the content of the description, the present invention relates to one or more of the items as listed below:

[0055] 1.- A composition for manufacturing an engineered stone, said composition comprising a binder and a mineral filler, wherein said binder represents less than 15 % on a weight basis of the composition wherein: said mineral filler comprises one or more feldspathoid; and / or said mineral filler comprises a feldspar.

[0056] 2.- The composition according to item 1, wherein said feldspathoid can comprise general formula ZAlSixOywhere: Z can be selected from the group comprising K, Na, Ca, Li; X can assume any integer value between 1 to 6; and Y can assume value 4, 6, or 10. 3.- The composition according to item 1 or 2, wherein said feldspathoid can be selected from the group comprising, preferably consisting of: leucite (KAlSi2Oe), nepheline ((Na,K)AlSiO4), petalite (LiAlSi40io), kalsilite (KAlSiC ).

[0057] 4.- The composition according to any of the preceding items, wherein said feldspathoid in the composition mainly comprises or consists of nepheline.

[0058] 5.- The composition according to item 4, wherein nepheline can comprise the following general composition expressed in percentage by weight: SiCh 58 - 62 %; AI2O3 20 - 25 %; Na2O 8 - 12 %; K2O 2 - 6%; CaO 0 - 2 %; MgO 0 - 1 %.

[0059] 6.- The composition according to any of the preceding items, wherein said feldspathoid can represent at least 70% of the total weight of the composition, preferably at least 80% of the composition.

[0060] 7.- The composition according to any of the preceding items, wherein said feldspathoid can represent 50% or more, possibly 60% or more, even more preferably 70% or more of the weight of the mineral filler.

[0061] 8.- The composition according to any of the preceding items, wherein feldspathoid can represent 100% or less of the weight of the mineral filler, preferably 90% or less, possibly 80% or less of the weight of the mineral filler.

[0062] 9.- The composition according to any of the preceding items, wherein said feldspathoid comprises an amount of free crystalline silica below 5% based on the entire weight of the feldspathoid.

[0063] 10.- The composition according to any of the preceding items, wherein in said feldspar Na and / or K are predominant above Ca. 11.- The composition according to any of the preceding items, wherein said feldspar comprises the following composition: SiCh 68 - 72 %; AI2O3 16 - 20 %; Na2O 6 - 10 %; K2O 1 - 5%; CaO 0 - 2 %.

[0064] 12.- The composition according to any of the preceding items, wherein said feldspar represents 20% or more, even more preferably 30% or more of the weight of the mineral filler.

[0065] 13.- The composition according to any of the preceding items, wherein said feldspar represents 80% or less of the weight of the mineral filler, preferably 70% or less possibly 60% or less.

[0066] 14.- The composition according to any of the preceding items, wherein the composition can comprise both a feldspar and a feldspathoid.

[0067] 15.- The composition according to item 14, wherein said feldspathoid can be predominantly over the feldspar in the composition.

[0068] 16.- The composition according to item 15, wherein said feldspathoid and said feldspar are present in the composition in a ratio between 1,5: 1 and 9:1, more preferably in a ratio between 2: 1 and 4: 1.

[0069] 17.- The composition according to any of item from 14 to 16, wherein the sum of the amount of said feldspathoid and said feldspar represent the between 95 and 100% of the mineral filler.

[0070] 18.- The composition according to any of the preceding items, wherein the amount of crystalline silica in the composition is less than 5% on a weight basis of the composition, preferably below 2%.

[0071] 19.- The composition according to any of the preceding items, wherein the binder can be a thermosetting binder, for example unsaturated polyester resin. 20.- The composition according to any of the preceding items, comprising an amount of binder above 5 % based on the total weight of the composition, for example said amount is comprised between 8 and 12 % of weight of the composition.

[0072] 21.- The composition according to any of the preceding items, comprising one or more additives, for example: crosslinker, for example styrene monomer; and / or catalyst, for example cobalt-based catalyst; and / or initiator, for example organic peroxide; and / or coupling agent, for example silane-based coupling agent.

[0073] 22.- The composition according to any of the preceding items, comprising one or more pigments, for example titanium dioxide.

[0074] 23.- The composition according to items 18, comprising pigment in an amount being at least 1,5 %, preferably at least 2 % based on the total weight of the composition.

[0075] 24.- A method for manufacturing a decorative element made of an engineered stone wherein said method comprises the steps of: providing a composition comprising at least a binder and a mineral filler on a carrier, preferably a mold; compacting said composition on said carrier, preferably by means of vibration and / or vacuum; curing said binder, preferably by means of heating, wherein said composition is according to any of items from 1 to 23.

[0076] 25.- A decorative element made of an engineered stone wherein said engineered stone comprises the composition according to any of the item from 1 to 23 and / or obtained by the method according to item 24.

[0077] The present invention is in no way limited to the hereinabove described embodiments, but such composition may be realized according to different variants without leaving the scope of the present invention.

Claims

Claims1.- A composition for manufacturing an engineered stone, said composition comprising a binder and a mineral filler, wherein said binder represents less than 15 % on a weight basis of the composition wherein: said mineral filler comprises one or more feldspathoid; and / or said mineral filler comprises a feldspar.2.- The composition according to claim 1, wherein said feldspathoid can comprise general formula ZAlSixOywhere: Z can be selected from the group comprising K, Na, Ca, Li; X can assume any integer value between 1 to 6; and Y can assume value 4, 6, or 10.3.- The composition according to claim 1 or 2, wherein said feldspathoid is selected from the group comprising, preferably consisting of: leucite (KAlSi2Oe), nepheline ((Na,K)AlSiO4), petalite (LiAlSi40io), kalsilite (KAlSiCU).4.- The composition according to any of the preceding claims, wherein said feldspathoid in the composition mainly comprises or consists of nepheline.5.- The composition according to claim 4, wherein nepheline comprises the following general composition expressed in percentage by weight: SiCh 58 - 62 %; AI2O3 20 - 25 %; Na2O 8 - 12 %; K2O 2 - 6%; CaO 0 - 2 %; MgO 0 - 1 %.6.- The composition according to any of the preceding claims, wherein said feldspathoid represents at least 70% of the total weight of the composition, preferably at least 80% of the composition.7.- The composition according to any of the preceding claims, wherein said feldspathoid represents 50% or more, preferably 60% or more, even more preferably 70% or more, of the weight of the mineral filler.8.- The composition according to any of the preceding claims, wherein feldspathoid represents 100% or less of the weight of the mineral filler, preferably 90% or less, possibly 80% or less of the weight of the mineral filler.9.- The composition according to any of the preceding claims, wherein said feldspathoid comprises an amount of free crystalline silica below 5% based on the entire weight of the feldspathoid.10.- The composition according to any of the preceding claims, wherein in said feldspar Na and / or K are predominant above Ca.11.- The composition according to any of the preceding claims, wherein said feldspar comprises the following composition: SiCh 68 - 72 %; AI2O3 16 - 20 %; Na2O 6 - 10 %; K2O 1 - 5%; CaO 0 - 2 %.12.- The composition according to any of the preceding claims, wherein said feldspar represents 20% or more, preferably 30% or more of the weight of the mineral filler.13.- The composition according to any of the preceding claims, wherein said feldspar represents 80% or less of the weight of the mineral filler, preferably 70% or less.14.- The composition according to claim of the preceding claims, wherein the composition comprises both a feldspar and a feldspathoid.15.- The composition according to claim 14, wherein the amount of said feldspathoid is predominantly over the feldspar in the composition.16.- The composition according to claim 15, wherein said feldspathoid and said feldspar are present in the composition in a ratio between 1,5: 1 and 9: 1, preferably in a ratio between 2: 1 and 4: 1.17.- The composition according to any of claims from 14 to 16, wherein the sum of the amount of said feldspathoid and said feldspar represent the between 95 and 100% of the mineral filler. 18.- The composition according to any of the preceding claims, wherein the amount of crystalline silica in the composition is less than 5% on a weight basis of the composition, preferably below 2%.19.- The composition according to any of the preceding claims, wherein the binder can be a thermosetting binder, for example unsaturated polyester resin.20.- A method for manufacturing an engineered stone (1) wherein said method comprises the steps of: providing a composition (10) comprising at least a binder and a mineral filler on a carrier, preferably a mold; compacting said composition on said carrier, preferably by means of vibration and / or vacuum; curing said binder, preferably by means of heating, wherein said composition is according to any of claims from 1 to 20.

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