Use of a system for for everyday maintenance of a hard floor surface of stone or stone-like material

Description

Technical field

[0001] The invention relates to the use of a hard surface maintenance system, primarily concrete (cement), terrazzo and granite floor surfaces, but also marble or limestone surfaces. More particularly, the invention relates to the use of a maintenance tool that is suitable for daily use to maintain a polished, hard floor surface.

Background of the invention

[0002] The use of the system defined in the preamble of claim 1 is known from Scotch-Brite (TM), Blue Floor Pad, TD103, May 1997, or Scotch-Brite (TM), Green Floor Pad, TD 106, March 1999.

[0003] In connection with the cleaning or light polishing of floor surfaces, it is known to use a pad in the form of a three-dimensional non-woven material. The pad is typically provided as a circular disc-shaped element which is detachably mounted on a circular support plate and which is rotated when used in a plane parallel to the floor surface, such that when the pad is brought into contact with the floor surface that is, it is lightly compressed by the pressure arising between the floor surface and the bearing plate. The support plate is typically powered by a motor and may be mounted on a support frame which may be pushed or pulled by a walking operator or which may be constructed as a self-propelled vehicle.

[0004] Such pads are made of fibers of an organic material, e.g. polyamide and / or polyester, in particular polyethylene terephthalate. In some cases, the fibers also include natural fibers such as walnut or coconut fibers.

[0005] The fibers of the disc are interconnected at their common points of contact by so-called melt bonding, in which the fibers are subjected to heat which causes the outer part of the fibers to slightly melt and thereby bond to each other.

[0006] Alternatively or additionally, the fibers may be interconnected at their common points of contact by impregnating the pad with a polymer resin, hereinafter referred to as "base binder".

[0007] The production of this type of non-woven disc is well known e.g. from US-A3537121, US-A-4893439, EP-A-0397374, GB-A-1348 26 and EP-B-0562919 and therefore does not require additional, detailed explanation.

[0008] US-A-3,537,121 discloses wheels for polishing surfaces of aluminum, plastic, wax and the like. US-A-3,537,121 also discloses the manufacture of such pads. According to US-A-3,537,121, an adhesive mixed with abrasive particles is applied to the wheel by passing the wheel between two squeezing rollers, one of which is partially submerged in a container with a mixture of bond resin and abrasive particles, after which the wheel is cured or dried. In this way, US-A-3,537,121 provides a pad that is completely impregnated with a binder and abrasive particles.

[0009] US-A-4893439 discloses a wheel for polishing the surface of floors or aluminum. The pad consists of fibers of an organic material and provides a loose, open non-woven structure and contains a bond to hold the abrasive particles to the fibers. The pad disclosed in US-A-4,893,493 has larger voids than the pad disclosed in US-A-3,537,121, which makes it more capable of absorbing contaminants and thus can be used for a longer period of time. The pad disclosed in US-4,893,493 is also fully impregnated using a binder and abrasive particles.

[0010] EP-A-0397374 discloses a pad for floor polishing machines which is also fully impregnated with a binder and abrasive particles.

[0011] Wheels of the above type are often used for the so-called "glossing", i.e. dry polishing (often on a daily basis) of very lightly worn surfaces at high speed (1500-3000 rpm) and at high speed (1500-3000 rpm). relatively little pressure to restore the polished surface. This type of treatment is commonly used for both vinyl and marble flooring. Suitable discs for this purpose are available from 3M® under the name "3M ™ Floor Pads" and have little or no effect on very hard floor surfaces such as terrazzo or concrete that have been used for an extended period of time .

[0012] EP-B-0562919 discloses a non-woven polymer fiber non-woven wheel which is fully impregnated with a binder containing a mixture of a curable plastic resin and abrasive particles ranging in size from 0.1 to 30 µm. As examples of the curable resins, phenolic resin, acrylic resins, melamine resin and urea resin are mentioned. Diamond is mentioned as one among several other examples of abrasive particles that can be used. However, according to EP

B-0562919, the pad disclosed in this application is suitable for the surface treatment of marble floors and only in combination with crystallization chemicals, which means that this treatment must be performed in the presence of a salt-forming acid containing liquid.

[0013] According to EP-B-0562919 there is also provided a pad obtained by passing a non-woven pad through the nip between squeezing rolls, one of which is partially immersed in the binder / abrasive particles mixture such that the binder and abrasive particles through the cylinder surface are introduced into the shield.

[0014] Since the pad disclosed in EP-B-0562919 is intended to be used in the presence of crystallization chemicals, the method described in EP-B-0562919 is actually a glazing method used to increase the stain resistance and durability of a marble floor. This method is not suitable for daily maintenance as it uses special crystallization chemicals, including acids, to react with the calcium present on the floor surface to form insoluble calcium salts. This method is usually used once in connection with the initial preparation of a polished marble floor, and then at intervals of 6-12 months. Thus, the method described in EP-A-0562919 is too complicated to be used on a daily basis.

[0015] The wheels mentioned in EP-B-0562919 are marketed by 3M® under the names "3M ™ 5200 Brown Stone Renew Pad" and "3M ™ 4000 Gray Stone Polish Pad" and are used to process marble in the presence of chemicals for crystallization at relatively low speeds (less than 250 rpm).

[0016] The need to use crystallization chemicals makes the polishing work more complicated, since the chemicals are to be applied to the surface with possible subsequent removal of excess chemicals, which also contributes to extending the polishing time. The handling and application of chemicals also generally pose a potential risk to the environment, and especially to the working environment.

[0017] A method of obtaining a polished surface of stone or concrete is also known, by using tools comprising grinding or polishing elements made of a plastic resin mixed with abrasive particles, i.e. diamond particles. As such elements are fixedly mounted on a normally rotating plate, they are not able to compensate for unevenness in the floor which can lead to uneven treatment of the floor surface or to scratching or staining the floor surface when the element is to contact the surface with increased pressure. Yet another problem is that debris such as sand grains, small stones or metal can stick into or near the elements and scratch the floor surface. After all, this type of tool requires a special mechanism capable of creating more pressure on the contact surface between the tool and the floor surface.

[0018] WO 03/075734 discloses a disc-shaped cleaning device comprising a nylon scouring material which is disposed on a rigid disc which houses grinding elements containing industrial diamonds in the recesses of the active scouring surface. A drawback of the device disclosed in WO 03/07534 is that it does not eliminate the risk of crumbs sticking into or near the grinding elements. Yet another disadvantage is that the tool is complex and therefore more easily damaged and more difficult and costly to manufacture.

[0019] Therefore, there is a need for an improved and simplified method and tool for the daily maintenance of hard surfaces. Preferably, the method should be simple to use, e.g. by persons who are not specifically trained in the preparation of floor surfaces, and the method should be suitable for use with conventional floor surface maintenance equipment, e.g. polishing machines etc. Tooling should also be easy, not too expensive, and the tools should be durable.

Summary of the invention

[0020] It is an object of the invention to provide an improved technique that completely or partially obviates the problems associated with known techniques and wheels. In particular, it is an object to provide a hard surface treatment system that is easier to use and that provides a significantly better result than the prior art solutions.

[0021] The invention is based on the idea that diamond particle abrasive particles provide a polishing effect which is far superior to that achievable with those abrasive particles which are used in the examples set out e.g. in EP-B-0562919 and that this polishing effect is so great that it eliminates the need for crystallization chemicals.

[0022] The invention is defined by the appended independent claim 1. Embodiments are set forth in the dependent claims and in the following description and drawings.

[0023] It is understood that the term "diamond" includes natural diamond as well as synthetic diamond and diamond particles coated with any suitable coating, eg silver.

[0024] In the present disclosure, the term "effective amount" is to be understood as an amount sufficient to achieve a measurable improvement in gloss, as compared to the same treatment with a liquid containing no crystallizing agent at all. The hosts known to be effective are about 1-2 liters of the crystallizing agent (containing 2-30% by weight of e.g. magnesium hexafluorosilicate) per 50 m2 of floor area for a single treatment operation. Hence, amounts known to be effective on an ad hoc basis range from about 0.4 g of magnesium hexafluorosilicate per m2 of floor area. However, it is also known that a crystallizing agent diluted e.g. in a ratio of 1: 100 is effective with repeated use, e.g. with daily or weekly maintenance. Thus, the amounts known to be effective in maintenance are generally from about 0.004 g of magnesium hexafluorosilicate per m2 of floor area. It will be appreciated that other types of crystallization agents exist, e.g., zinc hexafluorosilicate, hydrofluoric acid, and oxalic acid. It may therefore be necessary to adjust the values ​​given above so that they apply to the selected type of crystallization agent.

[0025] The combination of the flexible pad and the diamond particles compensates for unevenness in the surface and distributes the pressure applied to the pad evenly. Due to the flexibility of the disc, this connection also significantly reduces the risk of diamond scratching the surface.

[0026] The use of diamond particles as abrasive particles for polishing hard stone surfaces provides an effect that is the same or better than that obtained with conventional abrasive particles in both wet and dry conditions. In particular, the use of diamonds makes it possible to dispense with the crystallization agent and thus eliminate its handling.

[0027] The abrasive particles have an average diameter of from 0.1 to 30 gm, preferably between 0.1 and 15 gm and most preferably between 10 and 15 gm.

[0028] In one embodiment, the second portion is substantially free of diamond particles.

[0029] Since the abrasive particles are present in the portions of the pad that are not in contact with the hard surface do not fulfill any function, the wheels of the invention can be manufactured at a lower cost.

[0030] The flexibility of the pad eliminates or reduces the damaging effects that diamond abrasive particles might otherwise have on a hard surface. Consequently, the tool can be used and is especially effective on hard stone and stone-like surfaces such as granite, concrete, terrazzo etc.

[0031] In one embodiment, the pad includes a disc-shaped member having a thickness and a first surface, the abrasive particles being present on the first surface and down to a depth from the first surface, the depth being less than the thickness. such that the first part is on the first face and the second part is on the second face opposite the first face. By leaving the second surface free of abrasive and adhesive, the attachment of the disc to the Velcro fastener on the backing plate is facilitated.

[0032] In a second embodiment, the pad includes a disc-shaped member having a thickness and a first surface, the abrasive particles being present on a portion smaller than the entire first surface, such that the first and second portions reside side by side on the first surface. first surface. The second form facilitates the migration of dust and debris to the target.

[0033] The pad comprises an open, loose, three-dimensional nonwoven material containing a plurality of fibers that stick together at points of mutual contact.

[0034] The abrasive particles may be bonded to the fibers of the pad by a secondary binder. Thus, the fact that the abrasive particles are only present at the contact surface does not necessarily adversely affect the bonding of the wheel fibers.

[0035] As non-limiting examples, the secondary binder may be selected from the group consisting of phenolic resin, melamine resin, urea resin and epoxy resin.

[0036] In one embodiment, the secondary binder forms a plurality of discrete droplets whose maximum diameter is less than the average distance between the two points of interconnection of the fibers. Consequently, the fibers are not fully coated with a binder resin, which further facilitates the migration of dust and debris to the disc.

[0037] The wheel may further include second abrasive particles selected from the group consisting of graphite, tin oxide, silicon carbide, and alumina.

The pad is preferably provided in the shape of a circular disc with a diameter between 30 and 100 cm and an uncompressed thickness between 1 and 5 cm.

Brief description of the drawings

[0039]

Fig. 1a-1b show a wheel according to a first embodiment.

Figs. 2a-2b show a wheel according to a second embodiment.

Figures 3a-3b are enlarged photographs of a wheel of the present invention, before and after application of the binder and abrasive particles.

Figures 4a-4b show a diagram of a wheel according to the first embodiment and a portion of the wheel at an enlarged scale.

Fig. 5 is a sectional view of a floor surface treatment machine on which a pad according to the invention is mounted.

Character description

[0040] First, the description describes a tool suitable for use in the maintenance of hard surfaces, then the manufacturing method of the tool, and finally the various applications of the hard surface maintenance tool.

Referring to Fig. 1a, a pad 1 made of an open, loose, three-dimensional non-woven fiber material 2 is shown. The first face of pad 1 includes a portion P1 containing abrasive particles bound to the material by a secondary binder, i.e. the main purpose of which is to bind the fibers to the material. The disc 1 is circular in shape.

[0042] Referring to Fig. Ib, a cross-sectional view taken along the line S1-S2 in Fig. Ia is shown. As shown in Fig. Ib, the abrasive particle portion P1 is on the first surface A and occupies a space to a depth D which is less than the thickness T of the wheel 1. On the second surface B, on the other hand, there is a portion P2 in which essentially no abrasive particles and secondary binder.

[0043] By "parts" it is meant parts of the macrostructure of the wheel 1 and not parts of individual fibers.

Referring to Figs. 2a and 2b, a similar wheel 1 is shown, with the difference that there is part P2 'also on the first face A, in which part P2' is substantially free of abrasive particles and a secondary binder. .

[0045] In both embodiments, the abrasive particles are present throughout the secondary binder and the fibers are attached to each other by a primary binder and / or by melt bonding.

[0046] A description will now be given of manufacturing the pad 1 according to the embodiment discussed with reference to Figs. Ia and Ib.

[0047] A circular disc-shaped Tan Floor Polishing Pad from Glit / Microtron®, 20 inches (51 cm) in diameter, 28 mm thick and a weight of 157 grams, was used as a starting material. These types of discs are available from Glit / Microtron, Wrens, GA, o

USA. The starting density of the pad was 27 kg / m3. Fig. 3a is a microscopic photograph showing the pad prior to the application of the polymer resin / abrasive particles. In Fig. 3a, it can be seen that the fibers making up the pad are connected to each other at their points of mutual contact by a base polymer resin. The shield is flexible and resilient, and contains polyester and nylon fibers.

[0048] A homogeneous polymer resin mixture was prepared, which consisted of 200 g of PA resin 52-68 phenolic resin (available from Perstorp AB, Perstorp,

Sweden), 100 g of T-RÓD® ethanol (available from Alfort & Cronholm AB, Bromma,

Sweden) and with 20 g of LANDS LS600F diamond particles, 4-8 µm (available from Lands Superabrasives, Co., New York, NY, USA). Immediately before applying the mixture, 60 g of 65% p-toluenesulfonic acid (PTS) were added as a hardener.

[0049] The resin mixture was sprayed onto the first surface A of the polishing wheel using a standard compressed air spray gun (typically used for spraying paint). The pad with the uncured resin then weighed 173 grams. The pad was then placed in a hot air oven at about 120 ° C for about 20 minutes.

[0050] As a result, the target has the appearance shown in Fig. 3b which shows a microscopic photograph. Spheres or droplets 11 of the resin / particle mixture are formed along each fiber as well as between the points of interconnection between the fibers. The droplets are so distributed that the fibers to which they are adhered are not completely covered. A more vivid illustration of this is provided in Figs. 4a-4b, which show the target described above with reference to Figs. 1a-1b and an enlarged part of this target (Fig. 4b) in which droplets 11 of the resin / particle mixture are attached to the fibers.

[0051] In order to test the performance of a pad made as described above, comparative tests were conducted to evaluate two different 20 inch (51 cm) discs made as described above: a first pad referred to as "yellow" containing silver coated diamond particles 7-12 µm in size and a second disc, referred to as "green", containing normal diamond particles 3-6 µm in size. Two different commercially available wheels were used as a reference: a 20 inch (51 cm) 3M ™ 5200 Brown Stone Renew Pad and a 3M ™ 4000 Gray Stone Polish Pad, both available from 3M, St. Paul, MN, USA.

[0052] The tests were carried out on two different types of surfaces: Kolmarden marble (marble from the Kolmarden area near Norrkóping, Sweden) and K40 concrete. Each test was carried out in an area of ​​approximately 1 m using a Coor & Kleever Crystallizer 1250 KG floor surface treatment machine (available from Coor & Kleever, SA, Barcelona, ​​Spain) containing a single backing plate adapted to attach the disc to the 20 inch floor ( 51 cm) and rotating at a speed of about 175 rpm. The test consisted of polishing the surface for about 1 minute / m. The surface gloss was measured at several points on the area before and after each treatment using a Sanwal / Cenma IG-310 Glosschecker. The gloss value in the tables below is the average value for each area. High gloss is rated 80-90 °. The silk gloss is rated 50-75 °. Satin is rated 30-45 °. The rubbing effect is rated 20-25 °. Low gloss is rated 5-15 °.

[0053] Each surface was tested both dry and with water as a lubricant. Additionally, the concrete surface was tested with a crystallization agent

Coor Rosa / K-2 (available from Coor & Kleever SA, Barcelona, ​​Spain) as a lubricant, ie the crystallization chemical mentioned in EP-B0562919, because it contains magnesium hexafluorosilicate as the crystallizing agent. [0054] When 3M ™ wheels were tested, each surface portion was treated first with the brown wheel and then with the gray wheel.

Table 1: Tests performed with water as a lubricant on Kolmarden marble

<td>Shield</td><td>Brown</td><td>Grey</td><td>green</td>

<td>Initial gloss</td><td> 17</td><td> 17</td><td> 10</td>

<td>Liquid</td><td>Water</td><td>Water</td><td>Water</td>

<td>Final shine</td><td> 17</td><td> 35</td><td> 30</td>

Table 2: Tests performed without a lubricant on Kolmarden marble

<td>Shield</td><td>Brown</td><td>Grey</td><td>green</td>

<td>Initial gloss</td><td> 20</td><td> 25</td><td> 28</td>

<td>Liquid</td><td>Lack</td><td>Lack</td><td>Lack</td>

<td>Final shine</td><td> 25</td><td> 30</td><td> 50</td>

[0055] From Tables 1 and 2 it can be seen that on marble, which is a relatively soft stone with a hardness of about 3-5 Mohs and using water as a lubricant, the combination of 3M ™ (brown and gray) discs provides a slightly better effect. however, both the gray and the green wheels result in values ​​in the "satin" range. Under dry conditions, however, a significant improvement was achieved with the green pad, reaching the silk gloss range.

Table 3: Tests performed with water as a lubricant on K40 concrete

<td>Shield</td><td>Brown</td><td>Grey</td><td>Yellow</td><td>green</td>

<td>Initial gloss</td><td> 30</td><td> 29</td><td> 24</td><td> 35</td>

<td>Liquid</td><td>Water</td><td>Water</td><td>Water</td><td>Water</td>

<td>Final shine</td><td> 29</td><td> 29</td><td> 35</td><td> 46</td>

Table 4: Tests performed without the lubricant on K40 concrete

<td>Shield</td><td>Brown</td><td>Grey</td><td>Yellow</td><td>green</td>

<td>Initial gloss</td><td> 29</td><td> 34</td><td> 30</td><td> 48</td>

<td>Shield</td><td>Brown</td><td>Grey</td><td>Yellow</td><td>green</td>

<td>Liquid</td><td>Lack</td><td>Lack</td><td>Lack</td><td>Lack</td>

<td>Final shine</td><td> 34</td><td> 35</td><td> 48</td><td> 58</td>

[0056] From Tables 3 and 4 it is noted that under wet conditions and on a K40 concrete with a Mohs hardness of about 6-7, the combination of the brown disk and the gray disk did not provide any measurable improvement at all, while the combination of yellow and green shield provided a clear improvement. Under dry conditions, a slight improvement was seen for the surface treated with the combination of the brown wheel and the gray wheel, while a substantial improvement was seen for the surface treated with the combination of the yellow wheel and the green wheel.

<td colspan="2">Table 5: Design tests Coor Rosa / K-2 as Wed.</td><td colspan="2">Ie using an ice floe cleaner and; concrete sliding block K^with</td><td rowspan="2">iation 0</td>

<td></td><td>Shield</td><td>Grey</td><td>green</td>

<td></td><td>Initial gloss</td><td> 41</td><td> 35</td><td></td>

<td></td><td>Liquid</td><td>VMC-Pink</td><td>VMC-Pink</td><td></td>

<td></td><td>Final shine</td><td> 45</td><td> 51</td><td></td>

[0057] From Table 5 it is noted that on concrete K40 some effect can be achieved with the gray pad and with Coor Rosa / K-2 crystallizing agent as a lubricant and that a certain degree of better effect can be achieved with the use of the green pad and using Coor Rosa / K-2 crystallization agent as a lubricant.

[0058] It is generally found that the wheel of the present invention provides a significant improvement over the prior art. This improvement is especially noticeable in dry conditions and on concrete.

[0059] Fig. 5 shows a section of a floor surface treatment machine 20 to which a pad 1 according to the present invention is attached, so as to define a contact surface 9 with a hard surface 8, which in this case is the floor surface. The disc 1 is mounted on a driven, rotatable support plate 4, which is usually transversely bearing and thus rotates in relation to the machine body 5 on which the drive unit 6 is located. In this embodiment, the machine has a handle 7 and is thus adapted to be held / pushed / pulled by a walking operator. It is conceivable that in other embodiments the floor surface treatment machine 20 may be e.g. a self-propelled vehicle with a support plate 4 which is adapted to mount the disc 1.

[0060] The above-described pad 1 and method can be used for the daily cleaning / maintenance of polished, hard surfaces such as stone, concrete or terrazzo floor surfaces using a floor surface treatment machine such as a scrubber / dryer combination machine, e.g. Nilfisk CR1300; single disc floor maintenance machines (low speed or high speed) such as the Nilfisk 510B or 545; polishing machines, e.g. Nilfisk SDH5120, BHS5120 or BHS7014, all of which are available from Nilfisk-Advance, Stockholm, Sweden.

[0061] The treatment of the floor surface is typically carried out by rotating the disc while it is in contact with the floor surface in a plane parallel to the floor surface. Typical rotation speed is between 50 rpm and 3000 rpm. However, lower and higher rotational speeds are not excluded.

[0062] As is clear from the above description, the first embodiment of the wheel of the present invention includes an open, loose, three-dimensional nonwoven material comprising a plurality of fibers that are interconnected at their common points of contact by a primary binder and wherein the abrasive particles are mixed with and applied to the first surface of the pad only, so that it is only partially impregnated by the binder / particle mixture. Alternatively or additionally, the fibers may be melt bonded to each other.

[0063] According to a second aspect of the pad, the binder / particle mixture is only applied to part of the first surface. This can be achieved by covering those parts of the surface to which the binder / particle mixture should not be applied.

[0064] In a third embodiment, the pad is completely impregnated with the binder / particle mixture, e.g. by using squeezing rollers as described in EP-B-0562919.

[0065] In a fourth embodiment, the abrasive particles are present in the material of the wheel.

[0066] The invention is not limited to the use of phenolic resin. Other examples of suitable resins include melamine, urea, epoxy and polyester resins.

[0067] Furthermore, the hardener may be selected from any hardener suitable for the type of resin selected. It is also possible not to use the hardener, e.g. by subjecting the pad to cure at elevated temperature and / or for an extended period of time.

[0068] A solvent (ethanol was used in the example) is also used, simply to reduce the viscosity of the mixture and thus to facilitate spraying thereof. Any suitable solvent may be used, and the use of a solvent may be excluded if the method of application so permits.

[0069] It is understood that the pad 1 including the secondary binder and abrasive particles as described above may be connected to the disk or to a plate having any adapter for attachment to the support plate of a surface treatment machine or the pad may be adapted to attach directly to the machine. for surface treatment, using a system of Velcro hooks mounted on the support plate, which hooks engage with the fibers of the disc 1. Accordingly, the maintenance tool may consist of a wheel with a primary bond, a secondary bond and abrasive particles, possibly with the addition of dyes or printed areas providing information about the type of disk, manufacturer, trademark, etc.

[0070] Alternatively or additionally, the pad may be provided with a backing layer.