MXPA99009494A

MXPA99009494A - Method for producing nonslip floor coverings

Info

Publication number: MXPA99009494A
Application number: MXPA/A/1999/009494A
Authority: MX
Inventors: Wiedemann Gunter
Original assignee: Fraunhofergesellschaft Zur Foerderung Der Angewandten Forschung Ev 80636 Muenchen De; Sievers Thomas 21379 Rullstorf De
Priority date: 1997-04-16
Filing date: 1999-10-15
Publication date: 2000-07-01

Abstract

The invention relates to a method for producing nonslip floor coverings (1) made from mineral materials such as natural stone, fine stoneware, artificial stone or ceramics. The inventive method is carried out in two stages. In the first stage, micro-craters which are invisible to the human eye are created and statistically distributed on the surface of the floor coverings or slabs by means of pulsed laser bombardment. According to the invention, the surface of the floor coverings or slabs thus obtained are subsequently subjected to hydromechanical post-treatment, wherein the surface of the laser-structured floor covering or slabs are sprayed at least twice with a liquid (3, 8) e.g. inorganic acid or halogen hydrogen acid. The final spray process (8) is used to clean and/or neutralize previous spray liquids from the surface of the floor covering (1) or slabs. After each spray process, at least one further process occurs wherein the spray liquid is distributed homogeneously on the surface of the floor coverings or slabs and excess spray liquid is removed (12) from this surface. Subsequently, at least one drying process (15) is carried out.

Description

METHOD OF MANUFACTURING ANTIRRESBALAMTENTO FLOOR COVERINGS Description of the invention The invention relates to a method for manufacturing anti-slip floor coverings made of mineral materials such as for example natural stone, fine stoneware, artificial stone or ceramics. A special application area for the invention is to increase or produce an anti-slip effect in highly polished floors, especially those used in buildings or public buildings or in buildings or buildings accessible to the public, as well as in those areas where liquids of any kind can be used. fall to the floor. Slipping is one of the most frequent causes of accidents in Germany. The severity of such accidents is usually underestimated. To increase the safety of footwear products, the soles of shoes and floors must be designed in such a way that they are anti-slip or anti-slip. This is especially necessary where the means that cause slippage fall to the ground. In many areas of public life, but also in the private domain, it is usual to use polished stone, bright natural stone and artificial stone slabs as typical floor coverings in dry and wet areas and in REF .: 31529 transition areas. What is important here is to harmonize the anti-slip characteristics with the architectural aesthetics. The anti-slip effect evaluation is carried out in accordance with DIN 51097 (determination of anti-slip property - uncoated regions subject to moisture - inspection procedures - inclined plane) and DIN "51130 (anti-slip property determination - rooms work and work areas with increased slip hazard inspection procedures - inclined plane) by means of an inclined plane, however, there are also measuring tools for the non-stationary measurement of the coefficient of friction. [Fb 701 comparative study of the measurement non-stationary coefficient of friction in floors (Schriftenreihe der Bundesanstalt für Arbeitsschutz).] There are different methods to produce or increase the anti-slip or anti-slip properties of floors made of natural or artificial stone.The use of these methods is predominantly dependent on whether the floor cover goes to to be lying or already lying (internal area, external area, qrado of expected soiling, among other things). The most important methods will be described briefly below.

In abrasive blasting, the abrasive blasting materials corresponding to the desired roughness or roughness are driven against the surface under high pressure. The more or less hard abrasive blasting material leads to irregular wrinkling and severe dulling of the surface (DE 31 39 427). In torch flame cleaning, high-energy, combustible oxygen gas flares are produced with which the surface to be treated is heated briefly. Through the action of the flames, there is a burst of quartz in the upper region of the stone, also as a fusion of the stone portions which then solidify like glass and adhere to the surface in a relatively loose way ( DE 35 45 064). The granulation is carried out with the use of a granulation tool (granulation hammer) which is provided with a plurality of chisel (or bevel) points uniformly arranged. During a continuous movement of the workpiece, the granulation hammer is struck against the surface with a certain frequency (DE 39 33 843). The described methods or similar methods using abrasive elements or chisel-like tools lead in an admitted manner to an increase in the safety of the product for the footwear, but, like other surfaces, for example those that are less polished during the manufacture, also to a considerable loss of brilliance and thus a reduction in its aesthetic appearance. The coating of the surfaces in order to increase their anti-slip quality has the consequence that the treated surface is provided with protuberances (DE 33 42 266). This method does not admit any alteration of the visual characteristics, but it is only of limited durability since it is not possible to avoid abrasion. In the treatment by chemical attack of natural stone surfaces, especially feldspar portions are attacked by the effect of substances containing hydrofluoric acid. (Informationsblatt des Bundesverbandes Trittsicherheit, Abteilung Offentlich eitsarbeit). The damage only reaches a few microns, the quartz is extensively spared. The loss of brilliance depends on the duration of the action; The alteration of the overall appearance must be tested on a sample surface. However, this method is extensively limited to be applied to mineral floor coverings. The composition and chemical concentration must be adapted to the different types of covers. Due to the long reaction times and the need to maintain the exact concentration, this method can not be integrated to the manufacturing process of floor slabs or only with a very high expense. Where there is an inappropriate application and disposal of the substance containing hydrofluoric acid, there is an increased risk to the safety of workers and the conservation of the environment. In DE 195 18 270 or WO 96/36469, an anti-slip floor covering and a method of manufacturing thereof are also described, the anti-slip effect is obtained since a dense network of microcraters that are supposed to be invisible to the eye human, are produced on the surface of the floor covering, preferably polished slabs of natural fiber or fine stoneware by laser irradiation. This solution represents a clear improvement with respect to the prior art. However, an increase in the anti-slip effect, as is desirable, for example in certain humid areas, can be obtained in an admitted manner with laser irradiation by increasing the density of the craters and by expanding the lateral extent and depth of the craters. . However, what is disadvantageous is that there may then be a clear deterioration of the visual characteristics or a loss of brilliance. A further disadvantage is that an increase in the density or dimensions of the crater is related to a decrease in the speed of the process. Frequently the impulse power of the peak that can be obtained with a conventional pulsed laser is not enough to increase the dimensions of the crater. Thus, the object of the invention is to propose a method of manufacturing anti-slip floor coverings, with the help of this method an increase in the anti-slip effect can be obtained without having any disadvantageous deterioration of the typical surface characteristics on the one hand and on the other hand. On the other hand, there is no decrease in the speed of the process and in which all the advantages of laser structuring are retained with respect to other methods for providing an anti-slip surface. According to the invention, this object is obtained with a method according to one or more of the claims 28. It is essential here that the anti-slip floor covering obtained in a known manner according to DE 195 18 270 or WO 96/36469 is submitted to a continuous hydromechanical post-treatment. This post-treatment hydromechanical can be carried out preferably in the same installation directly following the laser treatment and while maintaining the same speed of process, by which the overall process, which comprises two stages of process (treatment of laser and hydromechanical post-treatment) can be carried out continuously. However, in certain cases, for example when the laser-treated floor coverings receive only the hydromechanical after-treatment at the installation site, it may also be favorable for the two stages of the process to be executed separately, that is, not continuous way Advantageous developments of this overall process are represented in patent claims 2 to 28. According to the method of the invention, the laser-treated surface of horizontally transported floor slabs or slabs is sprayed briefly at least once with a acid, preferably a slightly acidic liquid during continuous advancement of the slabs. After each of these spray or spray operations, the spray liquid is preferably distributed by means of brushes or brushes or a blade or wiper blade uniformly on the surface of the floor slab covers and the excess spray liquid is retired.

This uniform distribution is preferably effected in such a way that the spray liquid only remains in the depressions and in the microcraters produced by the laser treatment, but not on the polished surface of the floor or slab covers. Here, the dose of the liquid is chosen in such a way that it adds up to an amount corresponding to approximately the volume of the depressions and microcraters. As a result of the effect of the laser, the surface of the craters is microscopically very rough and thus very large in relation to the volume of the craters. This produces very good conditions in which the diluted acid can work in the craters produced by the laser treatment and in the micropores that, depending on the type of slab, are present despite the polishing. The pH value and the reaction time of the substantially diluted acids compared to the chemical design treatment of the floor coverings are selected according to the invention in such a way that the polished surface is not yet deteriorated, inside the Craters, due to good reaction conditions, parts of the surface are attacked by acid or etched and thus there is an increase -in volume. Preferably, those craters which are located in the region of the feldspar portions of the natural stone or slabs of fine stoneware are enlarged. It is important to mention at this point that the reaction time of the acid spray liquid depends on many factors, especially: the speed of the process the distance between the first and last of the "spraying operations that serve to clean the surface of operations It is important that the acid, which in individual application types can also be concentrated, only affects the depressions and microcraters without any deterioration of the rest of the polished surface. the subsequent short reaction time (preferably between 60 and 150 seconds) of the acid in the craters, the slabs are then sprayed again with a liquid, here at the highest possible pressure and applied by brush once more Corresponding to the pH value of the first liquid, the liquid to neutralize may consist entirely of water or it can also be slightly basic (for example diluted bleach). In this regard, an advantageous development may consist in the fact that the pH value of the operating liquid can be determined continuously and this value used as the control variable for the pH value of the spray liquid. By means of the mechanically stronger effect of the brushes or brushes in relation to the distribution of the acid, the residues that no longer belong to the particle stuck of the mineral components of the floor slabs and that would otherwise lead to a decrease in the possible volume of the crater, are eliminated from the craters at the same time. After the washing or neutralization process, the slabs are dried with hot air. A main advantage of the method according to the invention consists in the fact that, when using this method, the advantages of the laser-structured floor coverings and slabs are preserved and the anti-slip effect is markedly increased. The invention will be explained in greater detail by the following modalities, given by way of example.

Modality 1. The variant of the method according to the modality 1 is illustrated in figure 1. Floor slabs placed, made of fine stoneware and equipped with an anti-slip finish by means of a pulsed laser bombardment and measuring 60 x 60 x 1.5 cm they are subjected, in an installation, to a post-treatment according to the method according to the invention. The slabs 1 are here moved on a conveyor belt 2 at a relatively high speed of 3 m / min. A liquid 4 containing dilute hydrofluoric acid, with an acid concentration of 50% of the maximum possible, is applied to a slab surface 5 polished with the microcraters 6 by a spray beam 3 via a 58 cm wide nozzle array type hole. At a spacing of 10 cm in the direction of operation of the slabs behind the spray beam, a brush is located 0 rotating brush 7 with soft bristles. The brush or rotating brush 7 distributes the liquid 4 uniformly in the microcraters 6 and in the natural depressions of the slab 1 and simultaneously remove the superfluous or excess acid from the surface 5. At a spacing of 50 cm from the spray beam 1, a second spray beam 8 is located which applies to the tile surface 5 a diluted bleach 9 corresponding to the concentration of the acid used, in order to neutralize it. In a manner analogous to the spray beam 3, a rotating brush or brush 10 is also located behind the spray beam 8, however, it runs at a higher rotational speed and has a higher contact pressure. Thus, in addition to the distribution and intensification of the neutralization of the spray liquid 4, there is a simultaneous removal of the liquids from the depressions and from the surface of the slab. Directly behind the brush or brush 10, the slabs 1 run obliquely upwards at an angle of 30 and a jet of compressed air 11 is directed to the surface of the slab from a slot-like nozzle 12, against the direction of movement, to a 30 ° angle to the slab surface, this jet of air removes any residue of liquid remaining from the surface 5 and microcraters 6 and other depressions. After this, the slabs are dried (for example, removal of the remaining moisture from the possible pore spaces) by one or more hot air apparatus 13 and the slabs 1 are transported forward, for example to a packing station.

Mode 2. The variant of the method according to the mode 2 is illustrated in figure 2. From a workstation 14 in which the anti-slip finish is applied through the intended production of microcraters 6 by means of pulsed laser bombardment , the granite slabs 1 treated by laser, measuring 30 x 30 x 1 cm and in 2 rows one behind the other, that is with a total width of 60 cm, pass continuously on a conveyor belt 20 to the post section 21 -treatment. The feeding ratio of slabs 1, determined technologically by laser treatment, is 0.6 m / min. Within the drying section 16, the slabs 1 first pass under a spray beam 3, which is again equipped with a 58 cm wide row of nozzle-type nozzles, however, the nozzle holes They are smaller in diameter than those of Example 1 by a factor of 5. Here, a liquid 4 containing dilute hydrofluoric acid, with an acid concentration of 10% of the maximum possible, is sprayed onto the polished slab surface 5, with the microcraters and natural depressions 6. The total amount of liquid 4 sprayed is only 15% greater than the volume of existing craters and depressions. At a spacing of about 15 cm in the direction running behind the spray beam 3, a rotating brush or brush 7 with soft bristles is located. The axis of the brush or brush is in this case arranged at an angle of 80 ° to the front feeding device. The rotating brush distributes the liquid 4 uniformly to the microcraters and natural depressions 6 and removes excess liquid from the surface. At a spacing of, in this case, 1 meter of the spray beam 3, an additional spray beam 8 is located, which sprays on the tile surface 5 a diluted bleach 9 corresponding to the concentration of the acid used and the amount of spray , greater than the acid by a factor of 10. Directly behind the spray beam 8, there is also located here a rotating brush 10, in an arrangement analogous to 7. The brush or brush is equipped with harder bristles, runs a a rotational speed 10 times greater than that of the brush 7 and is pressed harder against the slab surface. The spray and brush beam 8 are mounted on a common device 14, the distance between which and the spray beam 3 can be adjusted. This is required at a given process speed in order to vary the necessary reaction time corresponding to the desired degree of intensification of the anti-slip finish and when taking into consideration the different slab materials. Following the last spray and brush application process, another spraying operation is carried out with water which is sprayed from a slit-type nozzle with a volume flow of 10 1 / min on the slab surface 5. What is obtained by this is that the possible remnants of the already neutral mixture of the liquids 9 and 4 and any possible residual remnants of mechanical contamination and residues are completely eliminated - from the surface 5 of the slab and from the microcraters and depressions 6. After this, the slabs run through a drying section 16, where the slabs are dried by hot air from the hot air devices 17 blown thereon and by infrared irradiation 18. Between the working area of the brush or brush 10 and slot-type nozzle 15 and between slot-type nozzle 15 and drying section 16 there are located in each case plastic cleaning blades 19 which act as squeegees for liquids. It is obvious that in each case after the individual wet sections (first and second processes of spraying and brushing, spraying operation) the liquids are collected separately and submitted to a post-treatment and after the corresponding preparation they are brought back into circulation or to the waste water removal system. It is noted that, with regard to this date, the best method known to the applicant to carry out the aforementioned invention is that which is clear from the present description of the invention.

Claims

Claims Having described the invention as above, the content of the following claims is claimed as property: 1. A method for manufacturing anti-slip or non-slip floor coverings made of mineral materials such as for example natural stone, fine stoneware, artificial stone or ceramics, in a two-stage process by means of pulsed laser bombardment, where they are produced, statically distributed on the surface of the floor covering, by means of the directed action of laser pulses, microcraters that act as suction cups and that they are invisible to the human eye, characterized in that in a second stage of the process, the surface of the floor covers structured by laser or slabs thus produced is subjected to a specific hydromechanical post-treatment, the hydromechanical post-treatment is carried out in such a way that the surface of the floor coverings structured by laser or slabs is sprayed with liquid at least twice, serving at least one spraying operation to corrode parts of the surface of the microcraters and thereby enlarging them, and the last spraying operation serves to clean and / or neutralize the surface of the covers or floor slabs of the previous spray liquids.
2. The method in accordance with the claim 1, characterized in that the hydromechanical post-treatment is carried out only in the depressions of the covers or floor slabs.
3. The method of compliance with the claim 2, characterized in that the mechanical post-treatment is carried out only in the microcraters produced by means of laser pulses.
4. The method according to one or more of claims 1 to 3, characterized in that after each spraying operation at least one process is carried out in which the spraying liquid is evenly distributed on the surface of the cover or floor slabs and the excess spray liquid is removed from the surface and finally at least one drying process is carried out. - > • The method of conformance with one or more of claims 1 to 4, cap_t ± eOzar ± > the pa? * - txata ?? - ^^ apA in such a way that the surface of the covers or floor slabs is sprayed twice with liquids, the second spraying operation serves to clean and / or neutralize the surface of the covers and / or floor slabs of the first spray liquid, after each of the first and second spraying operations a process is carried out in which the liquid is evenly distributed over the surface of the floor coverings and slabs and the dash liquid in 6. The method according to one or more of claims 1 to 5, characterized in that in one or more of the spraying operations which serve to corrode and thereby lengthen the surface of the microcraters, an acid is used as the spraying liquid. 7. The method in accordance with the claim 6, characterized in that an inorganic acid such as this acid is used. '' 8. The method of compliance with the claim 7, characterized in that it is used in halogen hydrazide like this acid. 9. The method of compliance with the claim 8, characterized in that hydrofluoric acid (HF) is used as this acid. The method according to one or more of claims 6 to 9, characterized in that the acid used is a dilute acid. 11. The method according to claim 1, characterized in that the acid used is an aqueous solution with a maximum concentration of 50% of its maximum concentration in water. .12. The method according to claim 11, characterized in that the acid used is an aqueous solution with a maximum concentration of 10% of its maximum concentration in water. The method according to one or more of claims 1 to 12, characterized in that at least the last spraying operation is carried out in such a way that the liquid from the preceding spraying operations is neutralized. 14. The method according to the claim 13, characterized in that the spraying liquid of the last spraying operation is neutral or basic. 15. The method of compliance with the claim 14, characterized in that the pH value of the spray liquid of the last spray operation is a maximum of pH 9. 16. The method according to the claim 15, characterized in that the spraying liquid of the last spraying operation consists of water (pH value = 7), the amount of water used is greater than the amount of spraying liquid in the immediately preceding spraying process. The method according to one or more of claims 1 to 16, characterized in that, after the last spraying operation, a process is carried out with the aid of which the spraying liquid of the last spraying process is eliminated of the surface, the depressions and the microcraters of the surface of the roofs or floor slabs without leaving any residue. The method according to claim 17, characterized in that the spray liquid from the last spraying operation is removed from the surface of the floor coverings or slabs by means of a gas flow which is characterized by high pressure and / or by a high flow velocity. The method according to one or more of claims 18, characterized in that, with the exception of the last spraying operation, the process of evenly distributing the respective spray liquid on the surface of the floor coverings or slabs is carried performed in such a way that the respective spray liquid remains only in the depressions or microcraters, however not on the rest of the polished surface. 20. The method of compliance with the claim 19, characterized in that, with the exception of the last spraying operation, the distribution of the respective spray liquid and the removal of the excess spray liquid is carried out by means of a brush application process and / or by a squeegee blade or cleaner. .twenty-one. The method in accordance with the claim 20, characterized in that, in the case of the brush application process, rotating brushes with soft bristles, a low rotation speed and a low contact pressure are used. The method according to one or more of claims 1 to 21, characterized in that, after the last spraying operation, the system for the uniform distribution of the spraying liquid or its mixing with the preceding spraying liquids is completely eliminated. of the polished surface of the roofs or floor slabs and the depressions and microcraters, this being possible, in this case, - to do it with the steps of the method of claim 17 or 18. 23. The method according to claim 22, characterized in that the uniform distribution is carried out by means of a brush or brush application process. 24. The method according to claim 23, characterized in that brushes or rotating brushes with high rotational speed and a relatively high contact pressure are used. 25. The method according to one or more of claims 4 to 24, characterized in that the final drying is carried out by means of hot air devices. 26. The method in accordance with the claim 25, characterized in that the hot air devices are supplied with hot exhaust air and filtering pulsed laser process extraction devices of the first stage of the method. 27. The method according to one or more of claims 1 to 26, characterized in that the overall method in its first and second stages of the process can be carried out continuously in an installation, in this case, The ekr of the overall process or the speed of the passage of floor coverings or slabs through the overall process or the entire installation, which includes the reaction times of the respective spray liquids on the decks or floor slabs, is determined by the speed of the first stage of the process (laser treatment), and because with the exception of the last spraying operation, strong undiluted acids are used in this case as the spraying liquid and the spraying liquid from the last spraying operation is adapted thereto. The method according to one or more of claims 1 to 27, characterized in that the pH value of the liquid flowing outward from the last spraying operation is measured and used as the regulating variable for the basicity of the last liquid of sprayed.