Patent Application
20060096210
The present invention relates to a tile suitable for covering walls and/or floors, comprising a container element and a filling material disposed inside the container element.
In particular, the present invention relates to a tile comprising a visible container element and a filling material disposed inside the container element.
The present invention also relates to a method and apparatus for producing the tile.
In particular, the present invention relates to an injection method and to apparatus comprising an injection system for producing the tile.
The filling material suitable for filling the tile of the present invention should, however, possess all of the following characteristics simultaneously:
a) it should be easily injectable, that is, it should have a setting time such as to remain in the fluid state throughout the injection period and to set only once the tile is completely filled, so as to avoid blockage of the injection system due to premature setting of the material inside it,
b) it should have a high degree of hardness, once formed inside the container element of the tile, thus enabling the tile to withstand stresses due to external loads such as, for example, those imparted by walking, for floor tiles,
c) it should be produced from easily-injectable components which can react with one another quickly once they are put in contact with one another, and which can form the filling material having the characteristics of points a) and b),
d) it should be non-toxic to avoid environmental problems,
e) it should have optimal adhesiveness in relation to the container element of the tile, that is, it should be capable of remaining firmly fixed to the container element without the aid of glue and without bending of the walls of the container element to prevent the filling material coming out,
f) it should be light to permit easy transportation, and
g) it should be inexpensive.
The problem underlying the present invention is therefore that of providing a filling material which simultaneously possesses all of the chemical-physical characteristics described above.
This problem is solved by a wall and/or floor tile comprising a container element and a filling material disposed inside the container element, characterized in that the filling material is a polymeric material having a Shore D hardness greater than 50 and a setting time, at ambient temperature, of more than 3 minutes.
Preferably, the filling material has a Shore D hardness of between 55 and 85 and a setting time, at ambient temperature, of between 5 and 15 minutes, even more preferably, the filling material has a Shore D hardness of 75 and a setting time, at ambient temperature, of 10 minutes. The setting time is calculated for a quantity of 1 g of material poured. The amount of material in fact affects the setting time; in general a larger quantity of material corresponds to a shorter setting time.
A preferred example of the polymeric filling material is that which is produced by the reaction of several components, hereinafter referred to as multi-component material.
Even more preferably, the polymeric filling material is that which is produced by reaction of two components, hereinafter referred to as two-component material.
Preferred examples of these two-component materials are polyurethane or polyurea.
Advantageously, the polyurethane is that which is produced by reaction of a polyol having a number of OH groups of between 80 and 500 mgKOH/g and a viscosity of between 200 and 200,000 cps, with an isocyanate having an NCO content of between 5 and 31%.
Even more advantageously, the polyurethane is that which is produced by reaction of a polyol having a number of OH groups of between 100 and 400 mgKOH/g, more preferably between 120 and 250 mgKOH/g, and a viscosity of between 2,000 and 10,000 cps, with an isocyanate having an NCO content of between 10 and 25%.
As a general guide, a person skilled in the art will appreciate that the number of OH groups in the polyol and the NCO content of the isocyanate will be regulated in a manner such that the two components react stoichiometrically.
Preferred examples of the polyols suitable for the present invention are polyols of the polyester and polyether types. Even more preferably, the polyols are polyether polyols.
Examples of these polyether polyols are those sold by The Dow Chemical Company under the name Voramer® MB 3102 (chemical type: polyether polyol initiated with glycerol), Voranol® CP 450 (chemical type: glycerol propoxylate polyether triol with an average molecular weight of 450) and Specfil® FC 252 (chemical type: dispersion of styrene-acrylonitrile in polyether polyol).
Preferred examples of isocyanates suitable for the present invention are aromatic isocyanates based on diphenylmethane-4,4′-diisocyanate (MDI) and toluene-2,4 (2,6) diisocyanate (TDI), and aliphatic isocyanates such as, for example, isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI).
Examples of these isocyanates are those sold by The Dow Chemical Company, under the name Voramer® MB 3503 (chemical type: diphenylmethane-4,4′-diisocyanate (4,4′ MDI)).
If the filling material of the present invention is a two-component polyurea material, it will be obtained by reaction of an amine having a number of OH groups of between 500 and 1000 mgKOH/g with an isocyanate having an NCO content of between 5 and 15%.
Even more advantageously, the polyurea is that produced by reaction of a amine having a number of NH2 groups of between 600 and 800 mgKOH/g with an isocyanate having an NCO content of between 7 and 10%.
As a general guide, a person skilled in the art will appreciate that the number of OH groups in the amine and the NCO content of the isocyanate will be adjusted in a maimer such that the two components react stoichiometrically.
Preferred examples of isocyanates suitable for preparing the polyurea are those described above for the preparation of polyurethane.
Preferred examples of amines suitable for preparing the polyurea are primary amines such as, for example DETA (diaminodiethyl toluene) and MOCA.
The above-mentioned polyols, isocyanates and amines may be used as such or may include additives such as, for example, pigments, flame retardants, inert fillers, catalysts and dehydration agents.
A preferred example of a pigment suitable for use in the filling material of the present invention is that having the international C.I. classification RED 48/4.
Examples of these pigments are those sold under the name of Plastotint LB Rosso 312 by Icap Sira Chemicals and Polymers S.p.A and under the name Rosso Repi Fiat 47549.
Preferred examples of flame retardants suitable for use in the filling material of the present invention are those selected from silicones, phosphorus derivatives, such as esters and ethers of haloalkyl phosphates/phosphonates, phosphate and phosphonate derivatives such as triethyl phosphate, diethyl ethyl phosphonate, tris mono-chloro-phosphate, melamine (2,4,6-triamino-1,3,5 triazine), aluminium hydroxides, halogen derivatives such as, for example, aromatic halogenated polyalcohols, cyclic halogenated hydrocarbons, halogenated aryl esters, and halogenated diols.
An example of a silicone-type flame retardant which may be used in the filling material of the present invention is that sold under the name of Antifoam 1500 by Dow Corning.
An example of a triethyl phosphate flame-retardant which may be used in the filling material of the present invention is that sold under the name of Eastman by Eastman Chemical BV.
An example of a catalyst which may be used in the filling material of the present invention is an amine such as that sold under the name DABCO® 33-LV (chemical type: tertiary amine) from Air Product Chemical Europe B.V., or diethanolamine.
Examples of inert fillers which may be used in the filling material of the present invention are compounds such as sulphates, carbonates, silicates, quartz powder and glass microspheres. Even more preferably, the inert filler is barium sulphate.
An example of a dehydrating agent which may be used in the filling material of the present invention is a 50% dispersion of zeolite in castor oil such as that sold under the name of Voratron® EG 711 by The Dow Chemical Company.
The filling material of the present invention is preferably deposited in the container element by a system for injecting the components into the container element.
In detail, the injection method of the present invention comprises the steps of:
a) introducing separately into an injector the components which are to form the filling material,
b) reacting the components of step a) only in the region of a mixer connected to the injector,
c) completely filling the container element with the mixture obtained in step b), and
d) causing the filling material to set in situ inside the container element.
The mixer of step b) is preferably a static mixing nozzle formed by a tube provided with internal obstacles for facilitating the contact of the components with one another.
The setting step d) is advantageously accelerated by conventional heating in an oven. Even more advantageously, the heating in an oven takes place at a temperature of between 100 and 150° C.
The tiles thus produced can be transported by the deposition of a glass-fibre fabric on the filling material.
The above-mentioned method is implemented by apparatus of the present invention comprising at least one supply head suitable for depositing, in the container element of the tile, the multi-component polymeric filling material, which is capable of setting after a predetermined period of time, upon mixing of the multiple components, at ambient temperature, the supply head comprising injector means provided with separate supply circuits for each of the multiple components, and the separate supply circuits converging in a single nozzle for mixing the multiple components, from which nozzle the filling material is supplied into the container element, in controlled manner, to form the wall and/or floor tile.
Further characteristics and advantages of the wall and/or floor tile, of the apparatus, and of the method used for filling the tile according to the present invention will become clearer from the description of some preferred embodiments, given below, by way of non-limiting example with reference to the appended drawings, in which:
As shown in
The container element 1 may have various shapes and sizes, for example, it is square with dimensions of 2×2 cm.
The container element 1 may also be made of various materials; it is preferably made of metal, even more preferably of stainless steel.
The container element 1 has an outer, visible surface la and an inner surface 1b which is to come into contact with the filling material 2.
The outer, visible surface 1a may be a smooth surface or may be treated by a printing process or an engraving process.
The inner surface 1b may remain smooth or may be treated to improve adhesion to the filling material 2.
Typical examples of these treatments are butter-finishing, for example, 80-grain butter-finishing, and pickling with solvents such as, for example, trichloroethylene or nitro solvents.
The container element 1 is preferably produced by conventional pressing techniques.
As shown in a preferred embodiment in
The tiles 10 of the present invention can easily be transported and deposited on the surface to be covered, by virtue of the deposition of a fabric, for example, a glass-fibre fabric, on the flat surfaces 2a of the filling materials 2 of a plurality of tiles 10 disposed adjacent one another.
Alternatively, the above-mentioned operations of transportation and deposition on the surface to be covered may easily be performed if a plurality of tiles 10 of the present invention are held together by a layer of the filling material 2.
The advantages of the wall and/or floor tile of the present invention are clear from the foregoing description.
One advantage is that the wall and/or floor tile of the present invention comprises a filling material having a Shore D hardness of at least 50. This enables the tile to withstand external loads without deformation of the container element, thus enabling the aesthetic shape of the latter to be maintained.
A further advantage is that the wall and/or floor tile of the present invention comprises a filling material having a setting time of more than 3 minutes, at ambient temperature. This allows the filling material to be in the fluid state throughout the time necessary to fill the container element completely and to be in the solid state only once it is in situ, that is, inside the container element. Moreover, this enables the container element to be filled by an injection system without the injection system being blocked because of premature setting of the material inside it.
A third advantage is that the wall and/or floor tile of the present invention comprises a filling material formed by easily injectable components which can react with one another rapidly (from about 3 to 10 seconds) once they are put in contact. Moreover, both the components and the filling material produced therefrom are non-toxic to the environment and do not require solvents for their reactivity.
An advantage is that the tile of the present invention is formed by a filling material which can adhere firmly to the container element without the need to interpose a layer of gluing material.
A further advantage is that the tile of the present invention is light and is made with inexpensive filling material.
An advantage is that the tile of the present invention is easy to produce.
Clearly, only a few embodiments of the wall and/or floor tile, of the method, and of the apparatus of the invention have been described and a person skilled in the art will be able to apply thereto all of the modifications necessary to adapt them to particular applications without, however, departing from the scope of protection of the present invention.
The following example serves to illustrate the present invention without, however, limiting it in any way.
Preparation of Filling Material
Component A: 60 p/w of diphenylmethane-4,4′-diisocyanate sold by The Dow Chemical Company under the name of Voramer® Me 3053, having an NCO content of 21%, a viscosity at 25° C. of less than 500 cSt, measured by the Cannon Fenske method, and a specific weight at 25° C. of 1.19 g/ml.
Component B: 100 p/w of polyol of the glycerol propoxylate polyether triol type sold by The Dow Chemical Company under the name of Voramer® Me 3102, having a number of hydroxyl groups of 169 mgKOH/g, and a viscosity at 25° C. of 3000 cps.
After being stirred, component A and component B were loaded into an injector of known type by a volumetric pump and were kept separated as far as the inlet to a mixing nozzle of a static mixer, formed by a tubular plastics body provided with internal obstacles for facilitating mixing of the components.
The mixing together of components A and B was thus S performed at ambient temperature and only in the region of the mixing nozzle, for a period of time equal to the time necessary to pass through the entire tubular body of the mixer and to reach the tile to be filled (3 to 10 seconds).
The mixture obtained was set after 3 minutes by heating to 120° C. in a conventional oven.
The polyurethane thus obtained showed the following characteristics:
Shore D hardness: 75-80 (measured by the ASTM D 2240 method), and
Density: 1.4 g/l (measured by the DIN 53420 method).
As shown in FIGS. 3 to 12, apparatus 20 for producing the wall and/or floor tile of the present invention comprises at least one supply head 22 suitable for depositing, in a container element 1 of a tile 10, a multi-component polymeric filling material 2 which is capable of setting after a predetermined period of time, at ambient temperature, upon the mixing of the multiple components. The supply head comprises injector means 24 provided with separate supply circuits 26 and 28 for each of the multiple components. The separate supply circuits 26 and 28 converge in a single nozzle 30 for mixing the multiple components, from which the filling material is supplied into the container element 1, in controlled manner, to form the wall and/or floor tile 10.
The apparatus 20 is suitable for supplying filling material into a container element 1 by means of a mixing nozzle 30 housed in a protective tube 32 comprising, at one end 32a, an opening which cooperates with a supply opening 30a of the nozzle and, at the opposite end, a ring nut 32b for fixing to a body 24a of the injector means 24.
The mixing nozzle 30 comprises a tubular body provided, at one end, with a supply opening 30a and, at an opposite end, with a receptacle 30b for collecting the multiple components emerging from the injector means 24 and conveying them into a mixing chamber 34.
The mixing chamber 34 comprises obstacles 36, shown schematically in
According to one possible embodiment, the apparatus provides for the separate supply circuits 26 and 28 of the injector means 24 to be closed by valve means 38 which bring about controlled opening and/or closure of the circuit.
According to one possible embodiment, the valve means 38 comprise closure members 40 which are constantly urged into abutment against valve seats 42 to close flow apertures 44 for the multiple components of the circuits. The closure members 40 can be opened pneumatically in controlled manner by pneumatic means 45.
According to one possible embodiment, the injector means 24 comprise an injection chamber 46, suitable for connection to the single mixing nozzle 30, and the separate supply circuits 26 and 28 converge in the chamber. Preferably, at least one partition 48 is provided in the injection chamber 46, and is disposed between outlets of the separate supply circuits 26 and 28, in a manner such that each component of the filling material comes into contact with another component only after reaching the nozzle 30.
According to a further possible embodiment of the apparatus, anti-drip means 50 are provided and comprise separate means for withdrawing, from the injection chamber, a predetermined quantity of each component which is not yet mixed, to prevent drips falling from the free opening of the nozzle.
Each of the anti-drip means 50 preferably comprises a diaphragm 52 which cooperates, in a leaktight manner, by means of a through-hole 54, with the injection chamber 46 and, on the opposite side, with a suction duct 56 suitable for creating a partial vacuum which, by deforming the diaphragm 52, draws the predetermined quantity of component which is not yet mixed, from the injection chamber 46.
In an advantageous embodiment of the apparatus, a plurality of supply heads 22 is provided (
According to a further embodiment, two pluralities of supply heads 22 are provided (
According to a further possible embodiment, the at least one supply head 22 is operatively connected to a plurality of separate supply ducts for each of the components for forming the filling material.
Moreover, each of the ducts may be heated, and each of the ducts may be heated to a temperature of between 20° C. and 40° C., preferably 30° C.
According to one possible embodiment, each of the separate supply circuits 26 and 28 is operatively connected to a pump 62 which is controlled in a manner such as to supply the component which is to form the filling material to each component-supply head at a predetermined pressure.
Preferably, each separate supply circuit is supplied at a predetermined pressure which is independent of the others. For example, the supply circuit is supplied at a pressure of between 20 and 70 atmospheres, preferably between 30 and 50 atmospheres.
According to one possible embodiment, one component is supplied at 30 atmospheres and a second component is supplied at 50 atmospheres.
Moreover, the separate supply circuits 26 and 28 may advantageously be arranged to be supplied at respective pressures such that, if the various components are supplied for the same period of time, when mixed, they form the filling material which has a shore D hardness greater than 50, and which sets, at ambient temperature, within a time longer than 3 minutes.
According to one possible embodiment, a reservoir 64 suitable for holding each of the components of the filling material is operatively connected to each pump 62. A stirring device 66 may advantageously be associated with each reservoir.
Moreover, the reservoir may be heated, for example, to a temperature of between 20° C. and 40° C. and preferably to 30° C.
According to one possible embodiment, a further store 68 for each of the components suitable for forming the filling material may be provided, operatively connected to each of the separate supply circuits 26 and 28.
Advantageously, the at least one supply head 22 is associated with a movement carriage 70 (
According to one possible embodiment, the carriage 70 is associated with sliding guides 74, preferably ball or roller guides.
Moreover, the carriage 70 may be operatively connected to actuators which are operated in controlled manner, preferably with position and/or velocity feedback.
According to one possible embodiment of the apparatus in question, each supply head 22 is operatively connected to a control unit 76 for bringing about controlled opening of the valve means 38. For example, the valve means 38 are opened for a period of time of between 0.3 and 150 msec.
Moreover, in one possible embodiment, in addition to working operations brought about in controlled manner, the carriage 70 adopts at least one rest position (
In a further embodiment of the apparatus, the carriage 70 has associated sensor means 78 for identifying the position of the carriage relative to a grating 80 for supporting and transporting at least one container element 1, the grating being disposed on a conveyor line 72 in a manner such that the nozzle is positioned so as to deposit the filling material 2 in the at least one container element 1.
Advantageously, a conveyor line 72 for at least one container element 1, which passes through an oven 82 suitable for accelerating the setting of the filling material, in series with positions for cooperation with the at least one supply head 22, may be provided.
More advantageously, a conveyor line 72 for at least one container element 1, which passes through positions in which the at least one container element 1 containing the filling material 2 cooperates with a device 84 suitable for depositing binding and reinforcing fabric on the rear of each tile 10, may be provided.
Optionally, a conveyor line 72 for at least one container element 1, which passes through positions in which it cooperates with a second oven for setting the filling material 2, is provided.
According to the possible embodiment shown in
In fact, an end 40a of each piston has a larger diameter than an intermediate portion 40b of each piston. The end 40a constitutes the actual closure member which is intended to abut the respective valve seat 42 to close the flow apertures 44 for the multiple components of the circuits.
The valve seat 42 comprises sealing rings 88 with inside diameters such as to permit leaktight sliding of the larger-diameter end 40a and to leave an outlet aperture relative to the smaller-diameter intermediate portion 40b.
The injection chambers 46 are separated from one another as in
The valve means 38 are operated pneumatically, in controlled manner, both during opening and during closure, by pneumatic means 45. According to the embodiment of
According to one possible embodiment, the piston 90 is connected to the rods of the pistons 40 by threaded connections 98.
According to one possible embodiment, the shell 92 also comprises means 100 for adjusting the stroke of the piston 90, the means 100 being constituted, for example, by an adjustment screw arranged in the base of the jacket 92.
In the embodiment of
These means comprise the adjustment means 100 and the configuration of the end 40a of the piston, as described below.
The position shown in
The ends 40a of the pistons abut the respective sealing rings 88, closing the component-flow apertures. the stroke of the piston 90, and hence of the pistons 40, to continue, giving rise to sliding of the lateral walls of the end 40a against the internal walls of the sealing rings 88. The further upward movement of the end 40a brings about the withdrawal of material from the injection chamber 46, thus preventing dripping.
According to one possible embodiment, the head 22 may also comprise means 102 for checking the wear of sealing rings 104 fitted along the sliding seats of the rods of the pistons 40.
These checking means 102 comprise, for example, an element 106 inserted in the body of the head 22 and provided with through-holes which define a portion of the sliding seat of the pistons 40. Each piston sliding seat comprises two sealing rings 104, one disposed on the actual body of the head 22 and the other disposed on the element 106.
The element 106 also has two ducts 108 which are put into communication with the exterior and which open into respective piston sliding seats, between the two sealing rings 104. If the sealing ring 104 disposed closer to the component-flow apertures 44 wears, the component thus returns along the sliding seat of the respective piston and emerges to the exterior along the respective duct 108.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IT02/00380 | 6/7/2002 | WO | 11/24/2004 |
