HK1193085B - Mixture, stone laminate and slab, based on volcanic rock particles, which can be used for construction and decoration, and production method thereof - Google Patents

Description

Mixture, laminate and panel based on volcanic rock particles, useful for building and decoration, and method for preparing same

Technical Field

The present invention relates to the field of building and decoration, and more particularly to the finishing and decoration of buildings, as it is a mixture of rock slices and slabs, which can be used for finishing and decoration of building surfaces and other objects. The invention also relates to a method for the production thereof. These products are made from volcanic rock particles.

Background

Volcanic rocks (volcanicrocks) have been a high value material due to their aesthetic appearance and due to the fact that they can be easily carved and cut by humans. This makes them short-lived and their use in modern buildings has become more expensive, thus making them a luxury product for use only in luxury buildings. These rocks are also known as igneous or clastic igneous rocks, e.g., rocks composed of fragmented volcanic products erupted from volcanoes in an outbreak event.

Soil erosion in mexico is partly due to quarry mining 71800 ten thousand tons of volcanic rock in total, which has caused environmental pollution in the national environment of over 3700 ten thousand tons of useless solid residues (INEGI, economic and ecological statistics, 2004).

Several panels are known which have the appearance of natural rocks, but these are only imitations: the fact that they are not rocks becomes apparent when we touch, smell and observe them. These slabs are commonly used in buildings made mostly of prefabricated building materials for the purpose of saving time and costs of installation.

In this category there are also slabs of aluminium, polystyrene and other materials with natural rock covering, obtained in limited size with respect to their weight and the slab supporting them. These rocks are adhered to the plate using synthetic adhesives, so the manufacturing method for preparing them is very costly, and their outer dimensions are limited by the size of the rocks from which they are obtained, so that the sheet and the manufacturing method are limited in size and shape.

Natural volcanic rock panels have existed for thousands of years, and their most important disadvantage is their weight, which makes them difficult to transport and set. Panels obtained from natural volcanic rock are generally relatively brittle when handled: the shock or impact may cause it to break. For this reason, they must be made thick enough so that they can be stronger and resistant to cracking. These panels often have a significant weight when they are placed on a wall, which makes it difficult or impossible to install without causing damage to themselves or the wall. The wall on which they rest must be strong and firm enough to support the weight of the panel. Even then, these sheets still present a risk of breakage due to the constant impact generated upon setting.

Due to the inconveniences mentioned above, there is a need for improved rock plates that can be used for decoration and are based on volcanic rock particles, and the present invention now provides these rock plates and their formulations and manufacturing methods.

Summary of The Invention

The present invention relates to various adhesive compositions and mixtures for forming articles for use as or in building construction.

In one embodiment, the present invention relates to an adhesive composition for making a laminate comprising an agglutinating agent comprising volcanic rock particles having a particle size of 1 to 5 microns and a polymer mixture in a combined amount sufficient to act as an adhesive for the other ingredients of the laminate; a silicate compound in an amount sufficient to stabilize the composition; and an amount of water to wet and fluidize the composition.

In this adhesive composition, the volcanic rock particles are present in an amount of 25% to 50%; the polymer mixture is present in an amount of 10% to 40%; and the silicate is present in an amount of 1% to 10%, based on the weight of the dry composition. Water is added to enable the composition to be combined with other materials to form a mixture for use in the manufacture of laminates. The mixture comprises the binding composition and a filler of solid particulate material of rock, plastic, glass, wood, metal or mineral.

Another embodiment relates to a preferred mixture for manufacturing a laminate comprising volcanic rock particles having a diameter of 1 micron to 3mm present in an amount of more than 50% of the mixture; an agglutinating agent comprising a polymer mixture in an amount sufficient to act as a binder for the rock particles; a silicate compound in an amount sufficient to stabilize the mixture; and an amount of water to wet and fluidize the mixture.

The rock particles are advantageously present in an amount of about 58 to 88% of the mixture and the rock particles are present in a plurality of different size fractions (size fractions), including a first size fraction having a size of 1 to 5 microns and being present in an amount of 18 to 28% by weight of the mixture; a second particle size fraction having a particle size of 0.25mm to 1.75mm and being present in an amount of 10% to 20% by weight of the mixture; and a third particle size fraction having a particle size of 2mm to 5mm and being present in an amount of 30% to 40% by weight of the mixture.

The agglutinating agent is preferably emulsified and is present in an amount of 8% to 25% by weight of the mixture. The agent comprises a water-dispersible block copolymer and a vinyl polymer in a weight ratio of 1:4 to 3:2, preferably 1: 1 to 2: 3. The water dispersible polymer powder comprises a block copolymer in an amount of 4% to 10% by weight of the mixture; and a vinyl polymer in an amount of 4% to 15% by weight of the mixture.

Preferred block copolymers are butyl acrylate and styrene copolymers and the vinyl copolymer comprises a combination of a vinyl acrylic co-polymer present in an amount of about 3% to 10% by weight of the mixture and a polyvinyl acetate resin present in an amount of about 1% to 5% by weight of the mixture.

The mixture further comprises a silicate compound to enhanceStability of the mixture. The compound is preferably hydrous magnesium silicate in an amount of about 1% to 5% by weight of the mixture. The silicate compound may also be kaolin, e.g. Al₂Si₂O₅(OH)₄。

The mixture includes water in an amount of about 15 to 30 weight percent to facilitate handling and mixing of the ingredients.

The invention also relates to articles prepared by forming one of these mixtures into the desired shape and drying the shaped mixture. The form may include a sheet, plate, tile, post or bundle having an outer surface polished to a desired finish (finish). The finished polished article may also be treated with a sealant. The article may comprise metal, glass, wood or fiber reinforcement, or may be provided on a plastic, wood, metal, inorganic mineral, ceramic or concrete substrate, optionally containing an adhesive for securing the article on the ground or construction. The articles may be prepared as interior or exterior structural components of buildings or other structures.

Another embodiment of the invention is directed to a method of preparing a mixture comprising providing water in an amount of about 0.1 to 0.4 liters per kilogram of volcanic rock particles and homogenizing the mixture. The agglutinating agent is preferably emulsified and the mixture is homogenized in a conventional mixer operating at 500 to 1000rpm for 30 to 120 minutes.

The homogenized mixture may be formed into a variety of different articles. The invention includes a method of forming a decorated rock article comprising forming a homogenized mixture into a desired shape and drying the formed mixture. The homogenized mixture may be formed into a desired shape by casting or molding. Typically, the dried mixture is polished to a desired finish, optionally followed by application of a sealant. The method further comprises forming the homogenized mixture on a substrate; polishing the dried mixture to a desired finish; and optionally providing an adhesive to the substrate to secure the article to the side of a floor, wall or structure. The material may also be used to form those portions of the structure.

Brief Description of Drawings

The details characterizing the volcanic rock particle-based mixture, slices and slabs for buildings and decoration, and the manufacturing method of the present invention are clearly described in the following description, as well as in the tables and the drawings, in which:

figure 1 is a graph illustrating the weight of the panels of the present invention compared to a commercially available product.

Figure 2 illustrates the performance of thermal conductivity between the plate of the invention and some commercially available products.

Figure 3 shows the resistance of the panels of the invention to hydrochloric acid and some commercially available products.

Figure 4 illustrates the installation time of the panels of the invention compared to some other commercial products.

Detailed Description

The present invention provides products made using the aesthetic and high aesthetic value of volcanic rock (i.e., igneous rock or clastic igneous rock), as well as waste produced by volcanic rock deposits found in limited areas of the world. When mining these deposits, large amounts of volcanic waste are generated and create a large environmental pollution due to the fact that the volcanic removed from the deposits cannot be used 100%.

The present invention now recycles this volcanic waste product to form a new and useful rock panel product. These products utilize waste produced when large pieces of volcanic rock are harvested to form artificial volcanic slabs having the same characteristics as natural volcanic slabs, thereby converting these wastes into volcanic slabs that replace 100% of natural volcanic slabs and have the advantages of non-polluting and lighter weight, in addition to the other attributes described herein.

The panels of the present invention have a variety of desirable characteristics. They have the same appearance, texture, color and odor as natural volcanic rock or large rock (dimensional rock), but they are at least 50% lighter than natural volcanic rock slabs. Because of the use of volcanic rocks having such properties, they are also resistant to acid rain (hydrochloric acid, sulfuric acid and nitric acid). They are resistant to ultraviolet radiation and can be used to shield these rays when desired. The plate is functional and can be easily and quickly mounted on any prefabricated or traditional element.

The invention relates to a mixture for producing rock pieces on solid substrates that can be used for construction and decoration, said mixture preferably being formed from volcanic rock particles, vinyl-acrylic copolymers, polyvinyl acetate resins, butyl acrylate and styrene copolymers, hydrated magnesium silicate and water.

The invention also relates to stone chips for decorating surfaces made from the above mixture. Another embodiment relates to a panel for use in construction and for decorating buildings, comprising the above-described rock laminate and a solid substrate.

Furthermore, the specific process for preparing the above mixture comprises i) mixing different volcanic rock particles in a conventional manner; ii) wetting the volcanic rock particles with 1 liter of water per 4kg of volcanic rock particles; iii) adding all of the vinyl-acrylic copolymer, polyvinyl acetate resin, butyl acrylate and styrene copolymer, and hydrated magnesium silicate, and iv) preparing a homogeneous mixture with a conventional stainless steel mixer at 500 to 1000rpm for 30 to 120 minutes.

The invention also includes a specific process for preparing the above-described panel, said process comprising: i) delimiting an area on the solid substrate where the rock laminate is to be laid, for which purpose a peripheral edge is provided on the solid substrate; ii) adding the mixture described in steps 1, 2, 3 and 4 in a homogeneous manner over the area delimited in the previous stage until the area inside the perimeter edge is covered; iii) allowing the mixture to dry open for a period of 24 to 72 hours; iv) depending on the type of trim: rough or smooth, rough grinding the board with a diamond cup (diamond cup); v) washing off all residues of the laminate, preferably by vacuum washing; vi) applying a layer of water repellent sealant to the sheet and vii) allowing the water repellent sealant to open dry for 3 hours. For faster curing, heat or other forms of energy, such as microwaves, may be used to dry the material.

Examples

The following examples show how the adhesive compositions and mixtures of the present invention can be formulated to make a variety of articles.

The present invention starts with volcanic rock particles obtained from waste and tests are performed to find the best combination of volcanic rock particles and agglutinating agent. The agglutinating agent is typically a copolymer that is commercially sold in the form of an emulsion as well as a resin. Water was also used to wet the particles and make up the volume of the mixture at a rate of 1 liter of water per 4kg of particles. The results are shown in table 1.

As can be seen in table 1, these tests show that the best combination of coagulants is the combination of butyl acrylate and styrene + polyvinyl acetate resin + vinyl-acrylic copolymer due to the higher plasticity imparted and shorter drying times and no significant cracking. The shortest acceptable drying time was found to be 72 hours, as no agglutinating agent was found to provide a drying time of less than 72 hours.

TABLE 1

Properties of several different agglutinating agents mixed with volcanic rock particles

Plasticity is measured on a scale of 0 to 10, with the highest value indicating high plasticity.

Once the optimal combination of agglutinating agents is found, the optimal amount or concentration of each component is determined by additional tests. Experiments were carried out for this purpose using different amounts of the individual components until the optimum dose was determined. The results of these tests are shown in table 2.

To impart greater water resistance to such mixtures, other components, particularly alkaline hydrated silicates such as hydrated magnesium silicate or kaolin, are added to provide a colloidal mixture similar to volcanic lava, but having the ability to adhere and melt on any material at room temperature and having the same physical characteristics as natural volcanic rock when dried, so that it can withstand the same finishing as natural bulk rock.

When analyzing the dosages of the different components of the mixture in question, it was found that when 10-40% of all the copolymers were used in combination with silicate and water, a significant amount of particles per square centimeter separated, with an optimum range of 1% to 10%, except for water (which correspondingly ranges from 1% to 20%).

When the copolymer and hydrous magnesium silicate are used at more than 40%, the appearance of the sheet is not ideal because the excessive amount of those additives causes the relief of volcanic rock particles. These dosages are not preferred for decorative purposes, although the resulting panels exhibit good hardness. These panels may be used in other applications, such as where abrasion or abrasion resistance is desired but a decorative appearance is not required.

TABLE 2

Providing different dosage properties of the mixture components

PD-isolated particles. Appearance is graded based on a score of 1 to 5, with higher values corresponding to better appearance; hardness was graded on a scale of 1 to 10.

It was found that the copolymer could be mixed with water (see table 3) and that fine volcanic rock powder obtained from crushed rock contained inorganic binders (inorganic functional minerals) which, when mixed with water and the butyl acrylate and styrene copolymer, changed, which gave it higher cohesion, adhesion and flexibility. With this combination, the substrate sheet can be laminated with natural volcanic rock, but when they dry, cracks are formed in the sheet, resulting in a sheet with low abrasion resistance and water resistance. Thus, when the resin in the polyvinyl acetate emulsion is added together with the vinyl-acrylic copolymer, the stability of the mixture is improved, thereby improving its adhesion, abrasion resistance and water resistance. Thus, the resulting panel exhibited no cracks or fissures.

TABLE 3

Percentage of inorganic binder of different volcanic rock particles

As seen in table 3, the best combination of volcanic rock particles was found to be a combination of 1mm to 3mm or 3mm +1mm +3 microns. In addition, a combination of 2mm +1mm +2 micrometers and a combination of 1mm +5 micrometers +1 micrometer or 1mm to 5mm +0.25mm to 1.75mm +2mm to 5mm also show excellent results, and thus these combinations are also considered in the present invention. However, for any particular formulation, the binding strength and appearance are considered to determine the optimum blend. In general, stronger bonding is obtained by using smaller particle sizes, while the appearance is judged on the basis of the absence of cracks or fissures (from evaporation of gases within the mixture during curing) and the resulting similarity to the green stone. Care must be taken that too many small particles create cracks, while larger particle sizes give the finished product a natural appearance.

Using the preferred mixtures disclosed herein, lamination was performed on a solid substrate and after several tests, the following methods were determined to be optimal: i) delimiting an area on the solid substrate where the rock laminate is to be laid, for which purpose a peripheral edge is provided on the solid substrate; ii) adding the mixture described in 1, 2, 3 and 4 in a homogeneous manner over the area delimited in the previous stage until the area inside the perimeter edge is covered; iii) allowing the mixture to dry open for a period of 24 to 72 hours; iv) depending on the type of trim desired: rough or smooth, rough grinding the plate with a diamond cup; v) washing off all residues of the laminate, preferably by vacuum washing; vi) applying a layer of water repellent sealant to the sheet and vii) allowing the water repellent sealant to open dry for 3 hours. The perimeter edge may be a rigid strip or slat whose height depends on the desired thickness of the rock laminate.

The method of preparing a mixture for making a rock laminate having the appearance of volcanic rock comprises the steps of:

i) the different particles forming part of the volcanic rock particles are mixed in a conventional manner.

ii) wetting the volcanic rock particle fraction with 1 liter of water per 4kg of volcanic rock particles.

iii) adding all vinyl-acrylic acid copolymers, polyvinyl acetate resins, butyl acrylate and styrene copolymers, as well as hydrous magnesium silicate, and

iv) mixing with a conventional stainless steel mixer, preferably at 500rpm to 1000rpm for 30 to 120 minutes.

Those skilled in the art will appreciate that these preferred conditions may vary as desired depending on the particular formulation and the final article to be prepared. For example, the speed and time of homogenization can be varied according to the final composition of the mixture, and these ingredients can be added in portions or all at once according to the size of the product to be prepared. The agglutinating agent is preferably emulsified prior to mixing with the other components. Furthermore, the drying or curing time of the final hardening conditions set for the mixture may vary depending on the amount of water added relative to the concentration of the other components.

The resulting mixture is substantially similar to cold volcanic lava, which has the property of adhering to and melting on any material. After drying, it has the same hardness and physical characteristics as natural volcanic rock, so we can apply the same finishing treatment thereto. Importantly, 90% of the formulation is from natural products.

The invention therefore also includes panels which can be used for decorating building surfaces and surfaces of other objects, where such slabs comprise rock slices made with the mixtures already described.

The panels obtained by the method shown in the present patent application are preferably solutions using natural rocks in modern construction works, which, due to their external dimensions, weight and structure, can never be covered by traditional panels made of natural volcanic rocks, because of the weight of the natural volcanic rock panels and the limiting factors of placement at a certain height.

This inherent characteristic of the panel makes it a product with many applications in the building industry and for decoration. Such a panel has all the advantages of natural bulk rock (never changing colour, having the appearance, smell and texture of natural rock) and is free from drawbacks in terms of weight, since it is a much lighter product (weight reduction up to 70%), and can be used as a building facade for buildings, shopping centres, schools, hospitals and houses. As a decorative element, it can be used for indoor and outdoor wall surfaces, and for ceiling light boxes. It can be used for an unlimited number of purposes, the only limitation being imagination. The mixture used to laminate the boards allows us to apply a gelatinous mixture, rather than having to use a mesh for adhesion, and as it dries, the rock melts with the material of the board used, forming a unique cohesion. Rough grinding with a diamond cup makes it look like a decorative large rock polished with a diamond disk.

The laminated varieties available on the panels are equal to the range of types and colors of natural rocks found in different volcanic deposits throughout the world.

The advantages of the panels discussed herein are further described below in conjunction with the accompanying drawings, which demonstrate that such results are not obtained by any of the conventional products. In particular, the weight of the panel is 70% lower than that made from natural volcanic rock alone. The appearance, texture, color and odor are the same as the panels made with natural rock alone. The panels of the present invention have flexibility and the ability to provide insulation, acid resistance, high temperature resistance, water resistance, protection against the action of bacteria, fungi and other moisture-related organisms and protection against UV radiation (i.e. their color never changes). The panel may also be used to provide sound insulation and it provides simple and quick installation on any type of heavy or light weight material.

These volcanic laminates can be used as facades for buildings, shopping centers, schools, hospitals and residences. As a decorative element, it can be used for indoor and outdoor wall surfaces, and for ceiling light boxes. It can be used for an unlimited number of purposes, the only limitation being imagination. One of their greatest advantages is the ease of installation, since they can be installed both indoors and outdoors with the same simplicity and by using the same conventional frames and screws for installing plasterboards. For outdoor use, they can be installed as easily as cement boards, and the same conventional frames and screws used for cement boards can be used. In the case of soffit, they can be installed as easily as ordinary soffit and use the same conventional system for their installation.

These slabs have other advantages over solid stone slabs: they can be directly adhered to the wall surface by screws, adhesives or mortar without having to use a frame. They can also be used to prepare furniture and decorative items such as tables and countertops.

It is important to emphasize the fact that: the previously described mixtures may be applied to solid body surfaces (e.g., containers, bottles, boxes, or any other solid surface) to decorate them. For this application, the surface must simply be cleaned, the mixture then applied by direct contact, it must then be dried and then coarsely ground. After the generated dust is washed away therefrom, a waterproof sealant is added, and the decoration of the object is completed with a rock laminate.

Because the final articles and products are preferably rock constructions, they can be used as load bearing or structural elements in building construction. The mixture may be consolidated as desired for these applications. The adhesive compositions disclosed herein and fillers of other solid particulate materials besides rock can also be used and still enable the manufacture of articles and laminates. Suitable alternative filler materials include plastics, wood, glass, metal or minerals. These filler materials may be of any size selected to provide an aesthetic or functional appearance or structure to the article or laminate.

The bonding composition is formed from components that can combine to retain the filler in a solid, dense product that can be formed into a desired article as a substitute for the rock laminate described herein. In particular, the adhesive composition utilizes a combination of volcanic rock particles having a relatively small particle size of 1 to 5 microns and a polymer mixture that functions together in a combined amount of adhesive that serves as the other component of the laminate layer. The amounts of these components are determined on a dry binder composition basis and the volcanic rock particles are present in an amount of 25% to 50% and the polymer mixture is present in an amount of 10% to 40%. Any of the polymer blends described herein for the blend can be used in the adhesive composition. Another component of the adhesive composition is a silicate of the type described herein and is used in an amount of 1% to 10% to stabilize the adhesive composition. These components are mixed together with an amount of water that wets and fluidizes the composition. Next, the adhesive composition is combined with the filler material. Typically, about 40 to 60 weight percent binder is mixed with about 40 to 60 weight percent filler to form a mixture, which can then be used to form a laminate or other article in the same manner as the rock mixture of the present invention.

The resulting products can vary according to the desires of the user, and they can be used in a number of different ways. The mixture itself can be cast onto the floor of the structure and allowed to dry, then polished and sealed to a final texture or finish. The tiles and panels may be formed by applying the mixture to a suitable substrate comprising any of wood, plastic, steel, aluminum, cement, ceramic or other support material capable of moving or transporting the poured parts to the desired location. The back side of the holder may include an adhesive for securing the tiles to the floor or wall. When relatively thin panels are used, screws or bolts may be used to secure these to the structure. Holes or holes may be provided in the panel for receiving bolts or other mounting hardware. Tiles or panels may also be secured to the steel structure, which is used to construct buildings with panels or tiles to provide a decorative finish to the building.

The mixture may also be shaped into an article by molding or casting into a desired configuration. In this way, various blocks, cubes, rods or other shapes can be prepared. The exposed surface of the article may be finished by polishing or not, depending on the final texture and finish desired. After the desired finishing is completed, a conventional concrete or ceramic sealant may be applied.

Various reinforcing materials may be used in forming the mixture into a product, including fiberglass, steel rods or planks, or may include fillers of wood, glass, ceramic, or other stone materials, depending on the desired appearance and strength requirements.

Due to the versatility and ease of application of the mixture, specific building products can be readily made, including walls, blocks or wall elements, fountains, pipes, windows or door frames, or other load bearing or decorative elements. These products are moisture resistant, acid or acid rain resistant, seawater resistant, and other environmental conditions, while their aesthetic qualities are maintained for many years due to their durable nature.

Claims (14)

1. A mixture for making a rock laminate comprising:

volcanic rock particles present in an amount of 58% to 88% by weight of the mixture, wherein said volcanic rock particles are present in at least three particle size fractions including a first particle size fraction having a particle size of 1 micron to 5 microns and present in an amount of 18% to 28% by weight of the mixture, a second particle size fraction having a particle size of 0.25mm to 1.75mm and present in an amount of 10% to 20% by weight of the mixture; and a third particle size fraction having a particle size of 2mm to 5mm and being present in an amount of 30% to 40% by weight of the mixture;

a agglutinating agent comprising a polymer mixture in an amount sufficient to act as a binder for the volcanic rock particles;

a silicate compound in an amount sufficient to stabilize the mixture; and

water in an amount to wet and fluidize the mixture.

2. The mixture of claim 1, wherein the agglutinating agent is emulsified, is present in an amount of 8% to 25% by weight of the mixture, and comprises a water-dispersible block copolymer and a vinyl polymer in a weight ratio of 1:4 to 3: 2.

3. The mixture of claim 2, wherein the water dispersible block copolymer in the agglutinating agent is present in an amount of 4% to 10% by weight of the mixture, and the vinyl polymer is present in an amount of 4% to 15% by weight of the mixture.

4. A mixture for making a rock laminate comprising:

volcanic rock particles having a diameter of 1 micron to 3mm and present in an amount greater than 50% of the mixture;

an agglutinating agent comprising a polymer mixture in an amount sufficient to act as a binder for the volcanic rock particles; and the polymer mixture comprises a water dispersible block copolymer and a vinyl polymer in a weight ratio of 1:4 to 3: 2; wherein the agglutinating agent is emulsified, present in an amount of 8% to 25% by weight of the mixture; wherein the water dispersible block copolymer is present in an amount of 4% to 10% by weight of the mixture and the vinyl polymer is present in an amount of 4% to 15% by weight of the mixture;

wherein the block copolymer is a butyl acrylate and styrene copolymer and the vinyl polymer comprises a vinyl acrylic copolymer present in an amount of 3% to 10% by weight of the mixture and a polyvinyl acetate resin present in an amount of 1% to 5% by weight of the mixture;

a silicate compound in an amount sufficient to stabilize the mixture; and

water in an amount to wet and fluidize the mixture.

5. The mixture of claim 1, wherein the silicate compound is hydrous magnesium silicate in an amount of from 1% to 5% by weight of the mixture.

6. The mixture of claim 1, wherein the water is present in an amount of 15% to 30% by weight of the mixture.

7. An article made by forming the mixture of claim 1 into a desired shape and drying the shaped mixture.

8. The article of claim 7 in the form of a sheet, plate, tile, column, or bundle having an outer surface polished to a desired finish.

9. The article of claim 7 comprising metal, glass, wood or fiber reinforcement, or supported by a plastic, wood or metal matrix optionally containing an adhesive for securing the article to the ground or building.

10. A mixture for making a rock laminate comprising:

volcanic rock particles having a plurality of different particle size fractions and present in an amount of 58% to 88% by weight of the mixture, wherein said volcanic rock particles are present in at least three particle size fractions including a first particle size fraction having a particle size of 1 micron to 5 microns and present in an amount of 18% to 28% by weight of the mixture, a second particle size fraction having a particle size of 0.25mm to 1.75mm and present in an amount of 10% to 20% by weight of the mixture; and a third particle size fraction having a particle size of 2mm to 5mm and being present in an amount of 30% to 40% by weight of the mixture;

a agglutinating agent comprising a polymer mixture in an amount sufficient to act as a binder for the volcanic rock particles; wherein the agglutinating agent is emulsified, is present in an amount of 8% to 25% by weight of the mixture and comprises a water-dispersible block copolymer and a vinyl polymer in a weight ratio of 1:4 to 3: 2;

a silicate compound hydrous magnesium silicate in an amount of 1% to 5% by weight of the mixture to stabilize the mixture; and

water in an amount of 15% to 30% by weight of the mixture to wet and fluidize the mixture;

wherein the sum of the contents of the components of the mixture is 100 percent.

11. The mixture of claim 10, wherein the water dispersible block copolymer in the agglutinating agent is present in an amount of 4% to 10% by weight of the mixture; and the vinyl polymer is present in an amount of 4% to 15% by weight of the mixture.

12. The mixture of claim 11, wherein the block copolymer is a butyl acrylate and styrene copolymer and the vinyl polymer comprises a vinyl acrylic copolymer present in an amount of 3% to 10% by weight of the mixture and a polyvinyl acetate resin present in an amount of 1% to 5% by weight of the mixture.

13. An article made by forming the mixture of claim 4 into a desired shape and drying the shaped mixture.

14. An article made by forming the mixture of claim 10 into a desired shape and drying the shaped mixture.