LU84663A1 - PROCESS FOR MANUFACTURING SLATE AND IMPROVED COVERING ELEMENTS - Google Patents

Description

The present invention relates to slates obtained from crushed slate waste and a synthetic re-sine serving as a binder. It also extends to covering elements of the slate type which, due to their mode of production, have improvements compared to natural slates.

In the production of natural slates, the amount of waste is generally up to 4 times greater than the quantity of slates produced, which explains the high cost of natural slates.

The object of the present invention is to manufacture slates from this waste in order to recycle them, thereby enabling a reduction in the cost price of a natural slate and the simultaneous production of slates of a new type.

According to a first aspect, the present invention provides a process for the manufacture of slates 20 characterized in that it comprises the following operating steps: - crushing and grinding of slate waste, - separation of the crushed and ground particles according to their particle size , 25 - selection of determined quantities of different particle sizes, - possible mixing of this load with a predetermined quantity of sand and then chalks, - addition of an adequate resin and hardener 30 to form a relatively fluid paste, - transfer of the said dough in a suitable mold heated to around 40 ° C. and - release from the mold after vibration of the mold and hardening of the dough.

According to a particularly advantageous embodiment, the solid filler, represented by natural materials, has the following composition: i 2 - from 18 to 24% by weight of slate particles having a particle size range between 16 and 28 mesh, - from 8 to 14% by weight of slate particles having a particle size range between 28 and 35 mesh, 5 - from 7 to 13% by weight of slate particles having a particle size range between 35 and 48 mesh, - from 6 to 12% by weight of slate particles having a particle size range between 48 and 65 mesh, - from 4 to 10% by weight of slate particles having a particle size range between 65 and 100 mesh, and - from 9 to 15% of particles having a particle size range between 100 and 200 mesh as well as from 5 to 11% by weight of sand, from 19 to 25% by weight of floury chalk, to which are added as a percentage of the weight of the solid charge * from 2 to 4% by weight Degussa HK hardener and 15 to 18% by weight of Degussa type 137o methacrylic resin.

Preferably, the solid filler has the following composition: 2 ° - 21% by weight of slate particles having a particle size between 16 and 28 mesh, - 11% by weight of slate particles having a particle size between 28 and 35 mesh, - lo% by weight of slate particles having a particle size between 35 and 48 mesh, - 9% by weight of slate particles having a particle size between 48 and 65 mesh, - 7% by weight of slate particles having a particle size between 65 and loo mesh, and 3 ° - 12% by weight of slate particles having a particle size between loo and 2oo mesh , as well as 8% by weight of sand, 22% by weight of floury chalk, to which are added as a percentage of the weight of the solid filler: 3 5 3% by weight of HK hardener from Degussa and 17.5% by weight of resin metacrylic type 137o i 35 from Degussa.

The mold is advantageously coated beforehand with a pre-layer consisting of a resin of the 1000 type from Degussa which is intended to form the surface protective layer of the slate.

The process of the present invention makes it possible to manufacture slates of all shapes, namely of conventional shape and of particular shape, as will be described below.

According to another aspect, the present invention provides a slate characterized in that it has a first surface generally affecting the shape of a rectangle, joined to the base of a second surface generally affecting the shape of a triangle, said slate comprising, on at least one of its faces, at the point of overlap by other slates after installation, a projecting element intended to support these other slates.

These slates may in particular have ribs and projections on one of the faces only, in which case they can be produced by simple molding. In certain particular cases, it may be advantageous to provide protrusions on one face of the slate, for example ribs intended to fit into corresponding recesses on the other face of a second neighboring slate covering the first. In such a case, the use of a molding press may prove necessary.

For reasons of clarity, the Applicant understands by "slate" and "natural slate '·, respectively, the imitation of slate according to the present invention and the conventional natural slate used for the coating of roofs or more or less vertical constructions and obtained by cleavage of natural products of a chist nature.

The use of a synthetic material according to the invention makes it possible, using a mold, to obtain particular slates, such as those mentioned / 4 above.

Advantageously, the synthetic material used consists of a mixture of synthetic resin added with a suitable catalytic system and of the ground sludge waste.

The present invention is obviously not limited to the aforementioned synthetic material; it is also possible to use any other moldable and hardenable material that is judiciously chosen, making it possible to obtain an imi-tation of natural slate, such as, for example, a resin supplemented with suitable pigments.

According to a particularly advantageous embodiment, the mixture has a filler / resin ratio more hardener of about 5. The filler consisting mainly of crushed slate waste may possibly contain up to 25% of chalk depending on the quality of resin used, the quality of the natural slate waste used and according to the characteristics of dough and finished product desired.

According to a preferred embodiment of the ardoi se according to the present invention, the projecting element is symmetrical with respect to an axis of symmetry centered on the slate, partially covers the surface of said triangle by forming a groove in the center , along the axis of sy-25 metrie, and partially extends over said first surface.

According to a first embodiment of the slate according to the invention, the side of the first rectangular surface, which is substantially parallel to the base of the triangle forming the second surface, has a dimension similar to natural slates, preferably * 'rence of the order of 20 cm.

According to another embodiment of the slate according to the invention, the side of the first rectangular surface 35 which is substantially parallel to the base of the triangle forming the second surface, has

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/ 5 a dimension which is a multiple of the corresponding dimension of conventional slates, the different units being separated by a groove formed in said first surface.

5 These slates can advantageously include perforations in suitable places intended to nail them to the roof, said perforations being covered by neighboring slates overlapping after laying.

lo The embodiments of slates according to the present invention have many advantages, which make the coating of large areas faster and more economical.

The use of moldable synthetic materials 15 makes it possible to form projecting elements serving as support for the slates partially covering them.

By giving a particular shape to these projecting elements (not visible after installation), it is possible to reduce the contact surface of the slates in order to avoid the rise of 2o water by capillarity. The groove obtained along the axis of the slate drains the water down the coated surface, such as a roof for example.

Preferably, the groove formed by a projecting element is closed off from the tip of the second trian-25 gular surface in order to avoid the rise of water by this route.

The reinforcement of the slate, produced by the projecting element, constitutes a support frame for the slate and it is in these parts that the perforations intended for the passage of the nails can be provided. This reinforcement 3o also makes it possible to reduce the thickness of the slates and therefore their weight as well as the material used for their manufacture. The effect of the weight being further reinforced by the use of lighter synthetic materials, we can therefore consider

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lighter frame constructions and building structures.

The present invention will be described in more detail with reference to the appended figures, in which I f 1- FIG. 1 represents a first embodiment of the slate according to the invention, and - FIG. 2 represents a second embodiment of execution of the invention.

The examples which follow and which refer to the abovementioned figures are obviously only given by way of illustration and therefore do not in any way limit the scope of the invention.

Slate waste is crushed in a cone-cone breaker and then crushed in ball mills.

" The crushed waste is separated according to its particle size by means of sieve separators. 16, 28, 35, 48, 65, 100 and 200 mesh screens, for example, are used for this separation. "16 mesh" means that there are 16 meshes or openings-15 tures per linear inch.

The particles thus separated are stored in silos respectively for the sieves indicated above. An additional silo contains sand, the particles of which have a diameter of approximately 15o.

2o Another silo, finally, contains chalk in the floury state, the particles of which have a particle size of approximately a few tens of μm.

Then, in a dry mixer, a mixture of the different solid fillers and a hardener is produced.

This solid charge is then stored in a silo, which is itself drawn off to a wet mixer, to which the correspondingly corresponding amount of resin is added. The quantities shown in the following table: 35 7

MATERIAL DIMENSION IN PARTICLES% BY WEIGHT

waste 16 to 28 mesh 21% of ar- 28 to 35 mesh 11% 5 bonds 35 to 48 mesh lo% ^ 00 ^ 48 to 65 nesh 9 * \ load 65 to loo mesh 7% solid loo to 2oo mesh 12% sand 8% lo chalk 22% t * „hardener 3% of the solid filler <resin 17.5% of the solid filler '15 Sand is advantageously used, since it consists of spherical particles ensuring better fluidity and consequently a better distribution.

The chalk is advantageously used for filling and coating given the fineness of the part-2o cules. The addition of chalk, however, also influences the resin content, since it reduces the harmful influence of graphitic materials included in natural slate fines. The chalk can obviously be replaced by any other filler ensuring the same properties.

25 The HK type hardener is preferably used

marketed by Degussa and a metacrylic resin of type 137o, also marketed by Degussa.

The paste thus formed after kneading is immediately dosed and introduced into a mold heated to 40 ° C. This tempered-3o crossed off at 40 ° C. is maintained by means of a pulsed air current and also by virtue of the exothermic reaction which occurs when the resin sets.

After introducing the dough into the mold, the latter is vibrated for about 2 minutes ^^^^ in order to rearrange the grains and expel undue air.

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The surface is equalized simultaneously by means of a scraper, for example. If necessary, an adequate pressure is also applied by means of a press in order to obtain more complicated molded forms. When the measurement of the temperature makes it possible to conclude that the exothermic reaction is complete (after about 20 minutes) the product obtained can be demolded.

The mold is then cleaned using a jet of compressed air and then dried. This drying is favored by the temperature of 40 ° C. of the mold.

The cycle begins again with the application of a separator at the bottom of the mold followed by a prelayer consisting of a looo-type resin from Degussa. This prelayer is -. intended to form the surface protective layer of the slate. The mold cycle lasts approximately 35 to 40 minutes.

Depending on the shape of the mold used, it is obviously possible to produce slates of any shape such as the conventional shape.

According to another embodiment of the invention, 2 ° can manufacture slates having the overall shape shown in perspective in FIG. 1. In this case, there are two geometrical forms constituting the slate which bear the general reference 1.

A first planar geometric shape is constituted by said first rectangular surface 2 joined to the base of a second essentially triangular surface 3.

The slate also has a projecting element 4 forming a groove 5 along the axis of the slate, said groove 5 being closed in the tip of the triangle. Said protruding 8o element 4 constitutes a reduced bearing surface for other slates staggered and partially covering it and extends slightly over the rectangular surface. This advantageous shape of the projecting elements avoids the rise of water by capillary action and constitutes a reinforcement of the slate making it possible to lighten its weight by reducing the thickness 6 to 3.5 mm. The perforation 7 intended to receive a nail for example is advantageously disposed in the tip of the triangular / surface and this even in the reinforced part pre- j ~> feeling a thickness of approximately 4.2 mm.

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Depending on the surface condition of the mold, the slate may have a more or less rough surface imitating natural slate as best as possible. Similarly, the edges can be cut or chamfered and the corners 5 can be rounded.

The broken lines 8 show another slate laid.

Figure 2 shows on a reduced scale another embodiment of the present invention. In this case the rectangular rectangular surface 2 consists of several units 11, 12, 13 separated from one another by a groove 14 imitating the joint between two slates of usual dimensions. The triangular surface 3 and the projecting element 4 generally have the same shape as in the previous case, but taking into account the difference in dimensions. In addition, the projecting element has, in its part extending over the rectangular surface on each side of the axis of symmetry of the slate, a hole (15) allowing additional fixing.

2o It should be noted that the invention is not linked to the forms of slate described and that any other form of protruding element giving the same advantages falls under the scope / of the present of the present invention.

Claims (13)

1. A method for the manufacture of slates, characterized in that it comprises the following operating steps: 5. crushing and grinding of slate waste. - separation of the crushed and ground particles according to their particle size, - selection of determined quantities of different particle sizes. lo - mixing of this possible charge with a predetermined quantity of sand and then chalk. - addition of a resin and a suitable hardener to form a relatively fluid paste. . . - Transfer of said dough into a suitable heated mold 15. about 40 ° C and - demolding after vibration of the mold and hardening of the dough. 2. Method according to claim 1 characterized in that the solid filler represented by the natural materials. - from 18 to 24% by weight of slate particles having a particle size range between 16 and 28 mesh, - from 8 to 14% by weight of slate particles having a particle size range between 28 and 35 mesh, 25. from 7 to 13% by weight of slate particles having a particle size range between 35 and 48 mesh, - from 6 to 12% by weight of slate particles having a particle size range between 48 and 65 mesh, - from 4 to lo% by weight of slate particles having a 2nd size range between 65 and 100 mesh, and • K - from 9 to 15% of particles having a size particle range between 100 and 200 mesh as well as from 5 to 11% eiï ppids of sand, from 19 to 25% by weight of floury chalk, to which are added as a percentage of the weight of solid filler 35 from 2 to 4% by weight of hardener HK of Degussa 4 and from 15 to 18 % by weight of metracylic resin of the 137o type from Degussa. r 11 Λ m. " 3. Method according to any one of the preceding claims, characterized in that the solid filler has the following composition: 5 - 21% by weight of slate particles having a particle size between 16 and 28 mesh - 11% by weight of slate particles having a particle size between 28 and 35 mesh - lo% by weight of slate particles having a particle size between 35 and 48 mesh - 9% by weight of slate having a particle size between 48 and 65 mesh -7/6 by weight of slate particles having a particle size between 65 and 100 mesh, and 15 -12/6 by weight of slate particles having a particle size between loo and 2oo mesh as well as - 8% by weight of sand, - 22% by weight of chalky chalk, to which are added as a percentage of the weight solid load - 3% by weight of HK hardener from Degussa and -17.5% by weight Degussa 137o methacrylic resin. 4. Method according to one of claims 1 to 2 characterized in that the mold is previously coated with a pre-layer consisting of a resin of the looo type from Degussa which is intended to form the surface layer of the slate. '5. Slate characterized in that it has a first surface (2) generally affecting the shape of a 3 3 rectangle joined to the base of a second surface “<I (3) generally affecting the shape of a triangle said ,. slate (1) comprising on at least one of its faces at the place of overlap by other slates after laying, a projecting element (4) intended to support these 35 I other slates. 'φ 6. Slate according to Claim 5, characterized in that it comprises on one face projecting elements or ribs intended to fit into corresponding recesses on another face of a second slate. 7. Slate according to one of claims 5 or 6 characterized in that it comprises a projecting element (4) which is symmetrical relative to an axis of symmetry centered on the slate, in that said projecting element covers partially the surface of said triangle 10 (3) by forming a groove (5) in the center, along the axis of symmetry and in that said projecting element * * partially extends over said first surface (2). 8. Slate according to any one of claims 5 to 7 characterized in that the side of the first rectangular surface (2), which is substantially parallel to the base of the triangle (3) forming the second surface, has a similar dimension. to that of natural slates, preferably 20 cm. 9. Slate according to any one of reven-20 dication 5 to 8 characterized in that the side of the first rectangular surface (2), which is substantially parallel to the base of the triangle (3) forming the second surface, has a dimension which is a multiple of the corresponding dimension of conventional slates, the different units being separated by a groove (14) formed in said first surface (2). 10. Slate according to any one of claims 5 to 9 characterized in that it comprises, at the appropriate places and in the projecting element, at least, a perforation (7) intended to nail it to the roof. , said perforation being covered by the other slates. after installation. 11. Slate according to any one of claims 5 to 10 characterized in that it has a thickness (6) of 3.5 mm and that the projecting element exceeds at least 0.5 mm, preferably 0.7 mm, the * »13 \) surface of the slate. 12. Slate according to any one of claims 5 to 11 characterized in that it consists of a synthetic material consisting of: 5. 17% by weight of slate particles having a size between 16 and 28 mesh, - 9% by weight of slate particles having a size between 28 and 35 mesh, - 8% by weight of slate particles having a size between 35 and 48 mesh, - 7% by weight of particles d slate having a dimension of between 48 and 65 mesh, of 6% by weight of slate particles having a dimension of between 65 and 100 mesji and 15. of 10% by weight of slate particles having a dimension between 100 and 200mesh as well as, - 6.5% by weight of sand, - 19% by weight of chalky chalk, - 2.5% by weight of Degussa HK hardener and 20. 15% by weight Degussa type 1370 methacrylic resin. 13. Slate according to any one of claims 5 to 11 characterized in that it consists of a synthetic material comprising an adequate pigment.