WO2014118762A1

WO2014118762A1 - Decorated concrete products

Info

Publication number: WO2014118762A1
Application number: PCT/IB2014/058774
Authority: WO
Inventors: Roberta Alfani; Michele DE LONGIS; Giuseppe MANGANELLI; Flavio RAMPINELLI
Original assignee: Italcementi S.P.A.
Priority date: 2013-02-04
Filing date: 2014-02-04
Publication date: 2014-08-07
Also published as: ITMI20130154A1; EP2951032A1

Abstract

The invention describes a decorated concrete product, characterized in that it comprises at least one marquetry produced through the steps of: a) carving one or more points of the product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of b") housing of a preformed material according to a pattern complementary to the pattern of said hollow seat.

Description

DECORATED CONCRETE PRODUCTS

Field of the invention

The subject of the present invention is a decorated concrete product particularly suitable for non-structural ornamental use, especially for applications with aesthetic and decorative purposes in integrated architecture.

Background art

The patent application MI2012A001818 by the same Applicant describes concrete products for non-structural ornamental use, in particular in slab form, produced by casting a fluid concrete composition in a mold wherein at least one insert in hydrophobic material previously fixed inside the mold remains incorporated as exposed marquetry in the product after removal from the mold.

Therefore, this process requires the characteristics of the decoration to be designed before producing the concrete product and consequently adaptation of the forming process of the product for each case, without it being possible to insert decorative inserts after hardening of the concrete composition and thus being able to transform an ordinary concrete product into a decorated one.

SUMMARY OF THE INVENTION

The object of the present invention is to produce a concrete product, in particular of the type for non-structural applications, decorated with ornamental patterns with high aesthetic quality, for example and preferably of the type obtained by casting a fluid concrete composition in a mold, without the conventional molding process in the mold necessarily having to be adapted specifically for the purpose of producing the decoration, as occurs in the case mentioned above.

To achieve this object, the present invention proposes a decorated concrete product, characterized in that it comprises at least one marquetry produced through the steps of: a) carving one or more points of the product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of b") housing of a preformed material according to a pattern complementary to the pattern of said hollow seat. Therefore, in its broadest sense, a decorated product of the invention can be obtained from any pre-existing concrete product, generally not decorated or having a decoration of a different nature.

In a particular embodiment, the present invention firstly proposes forming the product in a mold by casting or by compression molding and removing it after hardening, preferably according to the description in the patent application PCT/EP/067762 by the same Applicant; after a curing time required to develop mechanical strength, for example after 28 days, a) carving one or more points of the hardened product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of b") housing of a preformed material according to a pattern complementary to the pattern of said hollow seat.

For example, in the case of a panel or a slab, a finished product according to the present invention has on one or both faces one or more marquetries of different form and material, in order to form an ornamental pattern or an inscription. The concrete product of the invention is in particular suitable for non-structural ornamental applications, such as cladding or covering elements, of both horizontal type and vertical type, such as flat slabs, ventilated facades, signs, infill panels and decorative or cladding elements for internal walls.

Non-limiting examples of concrete products suitable for the purposes of the present invention are panels or slabs as described in the patent application PCT/EP/067762 by the same Applicant, wherein said first molding step is obtained by casting in a mold a fluid composition comprising a hydraulic binder, one or more aggregates, charges and additives including, for example, a

shrinkage reducing agent and a superplasticizer agent, and water. Products such as panels or slabs produced by compression molding are also suitable.

In relation to said first molding step, according to a preferred embodiment of the invention a metal mold for concrete applications is suitable, with an internal surface partly or completely covered with a material selected from polyethyleneterephthalate, polycarbonate, polyamide, polymethylmethacrylate, or other similar materials capable of giving the concrete product an elevated surface finish during the casting phase in the case of wanting to obtain a concrete surface with limited surface roughness.

The product thus produced is left to harden and removed from the mold. After a curing time required to develop the mechanical properties required for subsequent operations it is possible to proceed step a).

According to said step a) of the invention, the phase of carving the product surface according to the desired pattern and shape of the decorative marquetry is carried out.

In a first embodiment, in a concrete product according to the present invention said step a) of carving produces at least one hollow seat on at least one product surface.

In a further embodiment, said step a) of carving produces a hollow seat according to a flaring with an angle of about 45°, as shown in Fig. 1 of the accompanying drawing.

In a different embodiment, in a concrete product according to the present invention said step a) of carving produces a through opening from one side of said surface to the opposite side. In this case, in the finished product the same marquetry will be visible on both sides of the surface.

In order to obtain high precision in the carving useful for producing complex shapes, computer-assisted automatic carving means are preferably used, such as a water tool or a miller or the like, with a

numerically controlled processing system that carves the trace of the desired decoration with precision.

In relation to step b) according to the invention of filling said carved hollow seat for producing a marquetry according to such pattern, according to a first embodiment it consists of a step b') of in situ molding of material. In this way a suitable fluid material is cast into the carving which is capable of hardening subsequent to chemical reactions or physical processes, such as a change of state, for example selected from polymers and precursors thereof, waxes, bicomponent resins, concrete mortars and mixtures, or aerial and hydraulic binder-based mixtures. The carved hollow seat hence acts as a mold of the marquetry.

For example, a fluid concrete mortar is prepared, preferably of a different color than that of the product so as to accentuate the desired decorative effect, and it is cast until filling the carving, preferably wetted in order to promote adhesion between hollow seat and cast mortar. For the same purpose, it is also possible to use a substance that acts as adhesion promoter, such as acrylic dispersions with mineral charges. After hardening, the mortar that has filled the carved hollow seat flush with the surface forms the desired marquetry, producing the finished product.

According to a different embodiment, the step b) according to the invention of filling said carved hollow seat for producing a marquetry according to such pattern, consists of a step b") of housing in the carved hollow seat of a marquetry material preformed for this purpose according to a pattern complementary to the pattern of said hollow seat. To obtain this shape corresponding and complementary to the carved hollow seat the same system of carving according to the step a) is preferably used.

For example, if we wish to obtain in said step a) of carving a hollow seat according to a flaring with an angle of about 45°, as shown in Fig. 1 of the accompanying drawing, and a corresponding marquetry according to the step b"), a same miller can be used for cutting both the materials with blades angled at 45 degrees, according to a similar cutting program.

In this variant according to the step b"), the preformed marquetry is fixed into the carved

hollow seat either by interlocking, or with the interposition of a suitable adhesive, for example selected from bicomponent epoxy resins, cyanoacrylate, neoprene- based glues, silicones, concrete pastes, vinyl glues.

The material of which this marquetry consists varies in a wide range, and is for example a plastic material, such as fluorescent or non fluorescent polymethylmethacrylate, glass, cardboard, wood, metals, stone, ceramic, minerals, concrete materials and/or derivatives thereof, as a function of the final use of the product.

For the housing of marquetries in fluorescent polymethylmethacrylate, in particular it is preferable for said step a) of carving to produce a hollow seat according to a flaring with an angle of about 45° with respect to the vertical, so as to increase the fluorescent effect of the marquetry material.

BRIEF DESCRIPTION OF THE FIGURES

In order to better understand the characteristics and the advantages of the invention, some non-limiting examples are provided below with reference to the figures of the accompanying drawings.

Fig 1 shows a cross sectional and exploded schematic view according to the step b") of the embodiment described above.

Fig. 2 shows a plan view of a finished decorated product obtained according to the step b') of the different embodiment described above.

BRIEF DESCRIPTION OF THE INVENTION

With reference to these figures, Fig. 1 shows a concrete product 10 on the surface 11 of which said step a) of carving has formed a hollow seat 12 according to a pattern with trapezoidal section corresponding to a flaring with an angle of about 45° with respect to the vertical of such surface. With the same carving process a marquetry 13 with trapezoidal section was shaped, for example produced in fluorescent PMMA, with pattern and dimensions complementary to the pattern and dimensions of said hollow seat 12 and therefore suitable to be housed permanently therein by interlocking or with the interposition of an adhesive, thus forming the desired marquetry and the finished product comprising this marquetry. Fig. 2 shows, for example, a different marquetry 14 with curvilinear contour, incorporated in the center of a finished concrete product 10, produced according to the step b') of the different embodiment described above. This marquetry is obtained by casting of a fluid material which hardens subsequent to a chemical and/or physical process, of a different color to the surface of the product 0, inside a hollow seat carved on this surface according to said step a), until it is flush with the surface. After a suitable hardening time of this marquetry material, the product is finished.

The following examples of composition and preparation of a concrete product according to the invention illustrate the invention without in any way limiting the scope thereof.

EXAMPLE 1

The solid components shown in Table 1 below were mixed in a Hobart intensive mixer for 3 minutes.

Table 1

The liquid components, including the water, were subsequently added and mixing continued for a time of three minutes, as a function of the characteristics of the mixer.

A casting mold for concrete applications was used to form a 50x50 cm panel with a thickness of 5 cm. The fluidity enabled uniform filling of the mold even without using vibration to compact the cast mass. After 24 hours it was possible to remove the product from the mold to subject it to the curing phase, which took place in a vertical position in a temperature controlled chamber at 20°C and 55% relative humidity. After the time necessary to develop the mechanical strengths required for the subsequent operation, for example 28 days after molding, the panel was subjected to said step a). The hollow seat for the marquetry was obtained by cutting the surface with a computer-assisted water jet, producing a through opening for the whole of the thickness of the panel.

Molding of the marquetry was then carried out according to the embodiment that involves said step b'). A sheet of polycarbonate was placed over one of the two perforated sides of the panel in order to seal the through hole. The surface of the polycarbonate sheet that seals the through hole was treated with a suitable release agent, for example a Teflon-based spray; a freshly mixed pigmented bicomponent epoxy resin was then cast, taking care to fill the through carving perfectly flush with the surface. After hardening, the polycarbonate sheet was removed.

The product obtained is a panel with exposed marquetry of both faces, which can be used, for example, as a dividing panel for interiors.

EXAMPLE 2

Proceeding substantially as described in Example 1 , but using the components described in Table 2 below, a slab for a ventilated facade for aesthetic purposes was produced.

Table 2

The thickness of the slab, with dimensions of 60 x 100 cm², was 20 mm.

It was subjected to said step a). The carving process was carried out with a numerically controlled cutting system with a cutter tip with a depth of 5 mm. In order to improve the adhesion, or grip, an adhesion promoting primer was used, applied to the carving with a paint brush.

According to the step b'), a non photocatalytic concrete-based mixture of the same color, with lower brilliance than the concrete TX Aria Bianco Italcementi, was cast into the carving. The concrete mixture was cast perfectly filling the carving previously prepared in the slab so that it is flush with the surface thereof.

Example 3

The solid components shown in Table 3 below were mixed in a Hobart intensive mixer for 3 minutes. Table 3

The liquid components, including the water, were subsequently added and mixing continued for a time of three minutes as a function of the characteristics of the mixer.

A casting mold for concrete applications was used to form a 60x60 cm panel with a thickness of 10 mm. The fluidity enabled uniform filling of the mold even without using vibration to compact the cast mass. After 24 hours it was possible to remove the product from the mold in order to subject it to the curing phase, which took place maintaining it in a vertical position, in a temperature controlled chamber at 20 °C and 55% relative humidity. After the time necessary to develop the mechanical strengths required for the subsequent operation, for example 28 days after molding, the panel was subjected to said step a). The hollow seat for the marquetry was obtained with computer-assisted cutting of the surface using a cutter tip with blades angled at 45 degrees.

Molding of the marquetry was then carried out according to the embodiment that includes said step b"). The decorative marquetry was prepared using the same computer-assisted automatic cutting with a numerically controlled cutting system with a cutter tip with blades angled at 45 degrees, selecting fluorescent polymethylacrylate as material. The marquetry obtained, with a thickness of 3 mm, was bonded with epoxy resin-based adhesive, perfectly occupying the previously prepared hollow seat. The product obtained measured 60x60 cm with a thickness of 10 mm having a fluorescent polymethylmethacrylate decorative marquetry panel with a thickness of 3 mm exposed on one surface of product. Example 4

Proceeding substantially as described in Example 3, but using the components described in Table 4 below, a panel for a ventilated facade for aesthetic purposes was produced.

Table 4

The thickness of the slab, with dimensions of 60 x 100 cm², was 5 mm.

According to the description given in Example 3 but using a cutter with perpendicular blades, the slab was carved to produce a housing for the marquetry; the operation was carried out using a numerically controlled cutting system with cutting tip.

A stainless steel decorative insert was prepared using computer-assisted cutting with a numerically controlled cutting system with a laser tip. The insert, with a thickness of 2 mm, was housed in the hollow seat carved on the surface of the slab.

Example 5

Following substantially the same procedure described in Example 4, a shading panel was obtained.

The 40x40 cm panel was 2 cm thick; the housing for the marquetry was obtained as in Example 4.

The decorative marquetry was produced by computer-assisted water jet cutting, selecting marble as material. The 1 cm thick marquetry was housed in the hollow seat milled as described above so as to be flush with the unmilled surface of the panel.

Example 6

Following substantially the same procedure described in Example 3, a dividing panel for interiors was obtained.

The 50x50 cm panel was 5 cm thick; the housing for the marquetry was obtained by computer-assisted water jet cutting, producing a through opening.

The decorative marquetry was produced by computer-assisted laser cutting, selecting polymethylmethacrylate as material. The marquetry, with the same thickness as the slab, was glued into the seat bonding perfectly to the edges of the cut surface so as to be flush with both opposite surfaces of the panel.

Claims

1 ) A decorated concrete product, characterized in that it comprises at least one marquetry produced through the steps of: a) carving one or more points of the product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of b") housing of a preformed material according to a pattern complementary to the pattern of said hollow seat.

2) A product according to claim 1 , characterized in that it comprises at least one marquetry produced by the sequential steps of firstly molding the product in a mold by casting or compression and removing it from the mold after hardening; after a curing time, a) carving one or more points of the hardened product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of b") housing of a preformed material according to a pattern complementary to the pattern of said hollow seat.

3) A product according to claim 1 and 2, characterized in that said step a) of carving produces at least one hollow seat on at least one surface of the product.

4) A product according to claim 1 and 2, characterized in that said step a) of carving produces a through opening from one side of said surface to the opposite side.

5) A product according to claim 1 and 2, characterized in that said step a) of carving produces a hollow seat according to a flaring.

6) A product according to claim 5, characterized in that said step a) of carving produces a hollow seat according to a flaring with an angle of about 45°.

7) A product according to claim 1 and 2, characterized in that said step a) of carving uses computer-assisted automatic carving means, such as a water tool or a miller.

8) A product according to claim 1 and 2, characterized in that in said

step b') of in situ material molding, a suitable fluid material is cast into the carved hollow seat which is capable of hardening subsequent to chemical reactions, or changing to the solid state, selected from polymers and precursors thereof, waxes, bicomponent resins, concrete mortars and mixtures, aerial and hydraulic binder- based mixtures.

9) A product according to claim 1 and 2, characterized in that in said step b") of housing into the carved hollow seat a preformed marquetry material according to a pattern complementary to the pattern of said hollow seat, said marquetry consists of a material selected from plastic material such as fluorescent or non fluorescent polymethylmethacrylate, glass, cardboard, wood, metals, stone, ceramic, minerals, concrete material, and/or derivatives thereof.

10) A product according to claim 1 and 2, characterized in that in said step b") of housing into the carved hollow seat a preformed marquetry material according to a pattern complementary to the pattern of said hollow seat, the same system or program of the carving formed according to step a) is used for forming the marquetry.

11 ) A product according to claim 1 and 2, characterized in that in said step b"), the preformed marquetry is fixed into the carved hollow seat either by interlocking, or with the interposition of a suitable adhesive selected from bicomponent epoxy resins, cyanoacrylate, neoprene-based glues, silicones, concrete pastes, vinyl glues.

12) A product according to claim 1 and 2, characterized in that said step b"), the marquetry is formed of a fluorescent material seated into a hollow seat according to a flaring with an angle of about 45°.

3) A method of molding a concrete product according to claim 1 , characterized in that it comprises the steps of: a) carving one or more points of the product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of b")

housing of a preformed material according to a pattern complementary to the pattern of said hollow seat.

4) A method of molding a concrete product according to claim 2,

characterized in that it comprises the sequential steps of first molding the product in a mold by casting or compression and removing it from the mold after hardening; after a curing time, a) carving one or more points of the hardened product surface forming a hollow seat according to a predetermined pattern; b) filling said carved hollow seat for producing a marquetry according to such pattern, either by means of b') in situ molding of material, or by means of for b") housing of a preformed material according to a pattern complementary to the pattern of said hollow seat.