CH684679A5 - Non-slip plastic mat and processes for their preparation. - Google Patents

Description

1

CH 684 679 A5

2nd

description

The invention relates to a non-slip plastic mat and a method for its production. In particular, the invention relates to an elastic plastic mat that can be used as an insert for bathtubs, shower basins and the like, has a grained, structured surface on its top in the position of use, and is provided with suction cups on its bottom in the position of use prevent the plastic mat according to the invention from slipping on a smooth surface. The invention also relates to a method for producing such an elastic, non-slip mat from one or more different plastic materials.

DE-GM 8 029 732 discloses bathtubs or shower inserts and associated neck pads made of foamed plastic with a grain-like structured surface, which have suction cups on the underside. The suction cups prevent the suction cups from slipping in a tub in a satisfactory manner. Regarding the way of attaching the suction cups to the underside of the insert, DE-GM 8 029 732 does not provide any information except that the attachment takes place in a manner known per se.

DE-GM 7 721 240 describes a massage or cleaning mat that can be inserted in bath tubs in particular, which is also provided with suction pads on its bottom - in the position of use - which serve as an adhesive for attaching the mat to a base such as, for example, on the bottom of a bed Serve bathtub. No information can be found in the publication regarding the attachment of the suction cups to the underside of the mat.

DE-OS 3 020 961 discloses a bathtub insert which consists of several layers thermally connected by welding. To attach the bathtub insert to the bottom of the bathtub, suction cups are attached to a base film, for example by welding. The thermal welding of the suction cups to the base layer of such a bathtub insert requires a separate step in the manufacture of such an insert. This is extremely complex and makes such a deposit undesirably expensive.

DE-GM 946 837 describes a bathtub insert made of soft plastic, moisture-repellent materials, which also has suction cups on its underside for attachment to a smooth tub floor. These are fixedly or removably connected to the insert and, in a preferred embodiment, can be buttoned into the insert. However, this solution has the disadvantage that the perforations of the mat into which the suction cups are buttoned tear out due to frequent mechanical stress or due to a currently occurring strong mechanical stress and therefore do not allow the bathtub insert to be firmly fixed to the surface. In addition, the process for producing the bathtub insert described is very complex in terms of production technology.

An insert for shower and bathing facilities in the form of a mat-like structure, which has detachable suction cups for fixing to the surface, is also described in DE-PS 2 414 294. The mat consists of a perforated, mesh-like, flat support, which is coated with plastic and to which the suction cups are detachably attached. This bath mat - like the one described above - has the disadvantage that the suction cups can be partially or completely detached from the carrier and / or the underside of the mat in the event of a sudden mechanical load on the mat, and thus a secure connection between the mat and the substrate is not guaranteed.

From DE-PS 3 303 993 an elastic insert for bathtubs, shower basins and the like is known from a foamed plastic with suction cups on the underside, in which the suction cups are integrally connected to the foamed layer of the insert and consist of at least slightly foamed plastic. The foamed layer of the insert and the suction cups connected in one piece with it are provided with an airtight skin made of a non-foamed plastic which corresponds to the foamed plastic material. A disadvantage of this solution is that in the step of foaming the insert and the suction cups integrally connected to it, the foam formation is not sufficient. This makes the part too heavy and too stiff to still meet the usage requirements. In addition, the manufacture of such a part is so expensive that the product cannot be sold at a price that is still marketable. In addition, the sketched manufacturing process leaves too little scope for an attractive design of the surface, for example through coloring and / or printing.

The present invention has set itself the task of eliminating the disadvantages of the prior art. The invention is intended to provide easy and inexpensive non-slip plastic mats. In particular, plastic mats are to be provided which have suction cups securely fastened on their underside for fixing the plastic mat on a smooth surface.

The process suitable for producing these mats is intended to make it possible, with simple process steps, to ensure that the suction cups are securely fixed to the underside of the mats, in the direction of use. It should be possible to pull the raw mat material off a coiled web and pass it through a molding tool in which the suction cups are formed, at the same time fixed on the underside of the mat and the mat contour is cut.

This is achieved by a non-slip mat made of one or more compatible, flexible, thermoplastic high-polymer materials) with a non-slip top and suction cups on the underside, which is characterized in that the suction cups are molded onto the underside of the prefabricated mat.

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

2nd

3rd

CH 684 679 A5

4th

The invention also relates to a method for producing such a non-slip plastic mat, which is characterized in that the prefabricated material of the mat, which consists at least on the underside of a flexible, thermoplastic, high-polymer material A, is fed in web form to a mold in which the suction cups made of a compatible material B are molded in the thermoplastic state on the underside of the web segment under plasticizing conditions, and that the supplied web segment is simultaneously cut to the desired format of the plastic mat.

The non-slip mat according to the invention consists of one or more, compatible, flexible, thermoplastic high polymer material (s). Such materials are known from the above-mentioned prior art and include, for example, polyolefins such as polyethylene and polypropylene. Acrylic polymers such as polyacrylates and polymethacrylates, polyvinyl chloride, polystyrene, polyamides, polyurethanes and thermoplastically processable elastomers (EVA), and copolymers of such polymers as rubber-modified polyolefins [PP / EPDM (polypropylene / ethylene-propylene-diene terpolymers )] a. In certain cases, mixtures of different polymers are also suitable for the non-slip plastic mats according to the invention. Suitable plasticizers and additives can be added to the high polymer materials mentioned, which improve their properties in terms of flexibility, heat and chemical (in particular alkali) resistance, etc. in the desired manner.

For the non-slip mats according to the invention, it is possible to laminate or combine different polymers to form a layer structure. This can be particularly advantageous if a certain structure is to be applied to the surface of the mat in order to ensure the slip resistance against the feet slipping off. With regard to such laminates, there are no restrictions apart from their compatibility with one another.

Usually, the non-slip mat according to the invention has a strongly structured surface on its upper side, for example in the form of scars or embossments. Suction cups are molded onto the underside, as will be described in detail below, in order to be able to attach the mat to a suitable surface, for example the surface of a bath or shower tray, in a non-slip manner.

In a preferred embodiment, the mat can also have openings or holes which facilitate the passage or drainage of the water. These holes are arranged so that they do not undesirably affect the stability and tear resistance of the mat.

According to one aspect of the invention, the high polymer materials, from which at least the underside of the mat and the suction cups are made, are selected such that they form a common melt. Here, as in the following description and in the claims, it is understood that under the processing conditions (pressure, temperature) the polymeric material (s) melt in a narrow temperature range and are mixed together in the form of the common melt . When the mixed melt cools, a solid is formed which has equally good, if not better, mechanical properties compared to the unmixed polymers, and which stably connects the two parts of the mats according to the invention (underside and suction cups).

It is particularly preferred according to the invention that the suction cups of the non-slip plastic mat consist of an unfoamed high-polymer material and that at least the underside of the mat consists of the same material as the suction cups, but this material is foamed. This embodiment in particular ensures that when the suction cups are connected to the underside of the mat, in the process steps described in detail below, a common melt is formed under increased pressure and elevated temperature and this leads to a stable connection between the suction cups and the mat. This stable connection is particularly beneficial for the mat's slip resistance.

Examples of highly polymeric materials which are particularly preferred according to the invention on account of their advantageous properties and their longevity are polyolefins such as polyethylene and polypropylene and their copolymers and their mixtures. In such a case, the suction cups consist, for example, of one of the polyolefins mentioned, a copolymer or a mixture thereof, for example a polyolefin such as polypropylene in addition to a thermoplastic elastomer such as EPDM (ethylene-propylene-diene terpolymer), while at least the underside of the Mat, preferably the entire mat, consists of a web made of polyethylene or polypropylene and possibly also EPDM, which contains the usual additives, so as to impart the desired properties.

Another polymer which can also be used advantageously according to the invention is polyvinyl chloride. In this case, the web material regularly consists of a soft PVC foam sheet which can be used with or without a carrier. The suction cups are also made of soft PVC and are sprayed onto the underside of the web in the process described in detail below.

For at least the top of the mat, if a foamed polymer is used, the customary solid blowing agents are used, which are mixed with the polymers and then exposed to elevated temperature in conventional procedures for blowing up or foaming the polymer. The process steps for forming such foamed polymers are known as such from the prior art and therefore do not require any further explanation here.

According to a further aspect of the invention, the highly polymeric material from which little

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

3rd

5

CH 684 679 A5

6

least the underside of the mat, if not the entire mat, and the highly polymeric material from which the suction cups are made, bonded by means of an adhesive or primer 48. This is particularly advantageous if the polymers used have a chemically different composition and / or their physical properties differ greatly. Suitable adhesives depending on the polymers used are known from the prior art and include polyurethanes and acrylate polymers such as, for example, polymers of acrylic acid and methacrylic acid and their esters and their copolymers. In a further preferred embodiment, a primer is used in such a way that it is already applied to the web material which is fed to the molding tool or is applied to the web product immediately before the web material enters the molding tool.

Of course, the polymers of both the mat material and that of the material for the suction cups can contain further additives which modify their properties. These are also described in detail in the relevant prior art and include coloring substances, stabilizers and agents for increasing the chemical resistance, in particular the alkali resistance. There is also no detailed list here.

The method according to the invention is explained in detail below with reference to the figures. Show it:

1 shows a non-slip mat according to the invention, with the reference number 1 denoting the mat body and 2 the suction cups; the mat shown in FIG. 1 lies with the suction cups 2 upwards and thus shows exactly the opposite position compared to the non-slip plastic mat according to the invention when in use;

Fig. 2 shows - in an arrangement appropriate for use - a section through the non-slip plastic mat according to the invention, the actual mat body 1 pointing upwards and the suction cups 2 pointing downwards;

Fig. 3 shows a device with which the non-slip plastic mat according to the invention can be produced; and

FIG. 4 shows a section of the device according to FIG. 3, namely the actual molding tool with a feed roller for the web material, extruder for feeding the polymer granules and molding tool.

According to the invention, the method is characterized in that the prefabricated material of the mat, which consists at least on the underside of a flexible, thermoplastic, high-polymer material A, is fed in web form to a molding tool 4, 33 in which the suction cups 2 are made of a compatible material B. are injected in the thermoplastic state on the underside of the web segment 43 under plasticizing conditions, and that the supplied web segment 43

is cut to the desired format of the plastic mat at the same time.

The method preferably runs in several steps. In the first step of the method according to the invention for producing a non-slip plastic mat, as described above, the prefabricated material of the mat is fed in the form of a web to a molding tool 4, 33 of the device 3. For this purpose, the prefabricated mat material is wound up, for example, as web goods on a roll 31, 41 and consists of one or more of the polymers already described in more detail above.

According to an aspect of the invention already described above, at least the side of the mat which later becomes the underside of the product according to the invention consists of a flexible, thermoplastic, high-polymer material A. According to the invention, it is possible for the entire mat to consist of this material A. However, it is possible in the same way that one or more layers of the mat consist of a different polymer material as described above and only the underside of the mat consists of the flexible, thermoplastic, high polymer material A.

This material (“web goods”) is fed from the roller 31, 41 to the mold 33 via preferably driven take-off rollers 32, 42. Usually, as much material is drawn into the mold 33 as is processed in one machining step, i.e. shaped, provided with suction cups 2, cut and optionally also profiled and compacted at the resulting edges.

In a method step that runs parallel to the step of feeding the prefabricated web material, a preferably likewise thermoplastic high-polymer material B is fed to the molding tool 33 in a manner known per se. According to one aspect of the invention, this is selected such that it can form a common melt with the high-polymer material A. This has been described in detail above.

The high-polymer material B is introduced, for example, via a plasticizing unit 35, 44 provided with a filling funnel 34. The high-polymer material B, which is usually present in the form of pellets, granules or the like, is conveyed into the filling funnel 34 and flows from it via the gravitational force of the preferably heatable plasticizing unit 35, 44, in which a screw 45 kneads the material under the influence of heat and conveys it in the direction of the molding dies 46, 47 of the molding tool 33. The processing of the polymeric material B in the plasticizing unit 35, 44 takes place in a manner known per se from the prior art. If desired, additives such as plasticizers, coloring substances or the like can be added to the high-polymer material B in this processing step, which are intimately mixed with the polymer during the kneading of the polymer and, depending on the addition, influence its properties in the desired manner.

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

4th

7

CH 684 679 A5

8th

At the end of the screw flight of the plasticizing unit 35, 44 there is a molding die 46 which has shapes 461 corresponding to the later suction cups 2. The molten polymer is injected into these molds. The molds 461 corresponding to the suction cups are located in the die 46 of the molding tool 33 spatially opposite the underside of the web segment 43, which was supplied in the first method step described above.

When the two mold halves 46 and 47 of the molding tool 33 are pressed against one another, they contain a web segment 43 in the cavity formed in their center, which was fed in in the first method step. In the next step of the method, the suction cups 2 formed in the plasticizing step are molded onto the underside of the web segment 43 under plasticizing conditions. Temperatures are used which are in the range of the melting point or the melting points of the polymers used and which also depend on the particular polymers used. It is crucial that temperatures are used which, in accordance with the aspect of the invention described above, are conducive to the formation of a common melt of the two high-polymer materials A and B. Under increased pressure, the suction cups 2 formed by the extrusion in the corresponding molds 461 are firmly attached to the underside of the web segment 43. This creates a firm connection between the suction cups 2 and the underside of the mat material in a process-economical, inexpensive and safe manner, which later offers a high level of slip resistance of the non-slip plastic mat according to the invention.

Simultaneously with the step of molding the suction cups 2 onto the underside of the web segment 43 of the plastic mat, which takes place under plasticizing conditions, the mat is cut to the desired format. It is thus achieved in a simple manner that a further process step for setting the desired mat size can be omitted.

It corresponds to a preferred embodiment of the method according to the invention that for at least the underside of the mat and the suction cups 2 thermoplastic high-polymer materials are selected which are made up of a monomer which corresponds to the same basic type of monomer. According to the described aspect of the invention, this advantageous embodiment of the method achieves the use of highly polymeric materials A and B which can melt together and which, owing to the similar characteristics of the materials involved, then form a firm connection between the suction cups 2 and the bottom of the mat.

An even more preferred form of the process consists in selecting polymeric materials which are composed of the same monomers. Polymers whose maxima of the molecular weight distribution are in the same mass or number range are particularly suitable for this.

Even more preferred is the procedure in which the same polymers (A = B) are selected, of which the non-foamed high-polymer material is used for the suction cups 2, but the foamed high-polymer material is used for the mat body, or at least for its underside. In this context, the usual blowing agents known from the prior art are used.

According to the invention, the procedure has proven to be particularly advantageous in which soft PVC or a polyolefin is used as the highly polymeric materials. Of the polyolefins, preference should be given to polyethylene and polypropylene. These are, particularly preferably for the suction cups, advantageously also for the web goods, modified with other polymer materials, such as, for example, with EPDM (ethylene-propylene-diene ter-polymers). These, as well as the other high-polymer materials that can be used, can contain the usual additives, such as plasticizers, dyes or the like, in order to modify their properties in a manner appropriate to the application.

According to the invention, the method according to the invention is particularly preferably used for high-polymer materials in which the mat body or at least its underside consist of a PVC foam film and the suction cups 2 consist of soft PVC. Rubber-modified polyolefin, in particular polypropylene, and 2 polyolefins such as polyethylene, polypropylene or their copolymers or corresponding rubber-modified polyolefins and / or mixtures thereof according to the specification given above can also be used advantageously for the mat body and for the suction cups. For example, PP / EPDM (polypropylene / ethylene-propylene-diene terpolymers) are used for the web goods and for the suction cups.

The temperatures used for the plasticization and subsequent gating of the suction cups onto the underside of the mat should not or only slightly exceed the melting points of the polymers in order not to lead to degradation of the polymer or the polymers. Depending on the polymer used in each case, temperatures are usually used which, if at all, are only slightly above the melting range of the polymer or polymers.

Usually, the method steps according to the invention ensure that the suction cups 2 adhere securely and firmly to the underside of the mat, since the materials used for the two mat parts are highly polymeric materials which can form a common melt and combine optimally with one another on cooling.

This situation is shown in detail in FIG. 4. After the suction cups have been sprayed onto the underside of the web segment 43, the second molding die 47 of the molding tool 4, 33 moves from the first molding die 46 - driven by the opening and closing mechanism 36 of the molding tool.

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

5

9

CH 684 679 A5

10th

Tool 4, 33 - ab, and the corresponding finished and tailored web segment 43 is released and, if necessary, further processed in the manner described below.

According to a further aspect of the invention, such as, for example, when using certain polymers which are very different in their chemical and / or physical properties or for particularly secure connections between the underside of the mat and suction cups, adhesion promoters, so-called primers, can be used to impart adhesion between the underside of the mat and suction cups. Preferred examples of such primers are polyurethanes and acrylate primers, as have already been described above. These are intended to ensure an improved adhesion between the underside of the mat and the suction cups and also to connect polymers with one another, the chemical and / or physical properties of which do not allow a stable melt connection between the polymers, at least the underside of the mat and the suction cups. In a further, particularly preferred embodiment, one of the primers 48 mentioned is used in such a way that it is already applied to the web material which is fed to the molding tool or is applied to the web material immediately before the web material enters the molding tool.

It corresponds to a further preferred embodiment according to the invention to provide holes in the non-slip plastic mat which allow water to flow through. These are applied before or during the step with which the suction cups are sprayed onto the underside of the mat.

In a final process step, which can also be carried out in the molding tool 4, 33, but can also be carried out separately from it by special equipment, the edges of the mat or the edges of the water passage holes, which may also be additionally introduced, are pressed together with simultaneous heating and so compacted with the aim of preventing water from penetrating into the foam structure of the mat body. This step also prevents the edges from fraying and thus quickly wearing out during use.

Claims (19)

Claims 1. Non-slip mat made of one or more compatible, flexible, thermoplastic high-polymer material (s) with non-slip top and suction cups on the underside, characterized in that the suction cups are molded onto the underside of the prefabricated mat. 2. Mat according to claim 1, characterized in that the high polymer materials, from which at least the underside of the mat and the suction cups are made, are selected so that they enter into a common melt. 3. Mat according to one of the two claims 1 and 2, characterized in that the high polymer materials consist of the same basic monomer type. 4. Mat according to one of claims 1 to 3, characterized in that the high polymer materials consist of the same monomer. 5. Mat according to one of claims 1 to 4, characterized in that the suction cups consist of an unfoamed high-polymer material and at least the underside of the mat made of the same material as the suction cups, but is foamed. 6. Mat according to one of claims 1 to 5, characterized in that the high polymer material is polyvinyl chloride or a polyolefin. 7. Mat according to claim 6, characterized in that the high polymer material contains at least for the suction cups, but preferably also for the mat, in addition to polyolefins, in particular polypropylene, a thermoplastic elastomer, in particular EPDM. 8. Mat according to claim 1, characterized in that the high polymer materials, from which at least the underside of the mat and the suction cups are made, are connected to one another by means of a primer. 9. A method for producing a non-slip plastic mat according to one of claims 1 to 8, characterized in that the prefabricated material of the mat, which consists at least on the underside of a flexible, thermoplastic, high-polymer material A, fed in web form to a mold (33) is, in which the suction cups (2) made of a compatible material B in the thermoplastic state on the underside of the web segment (43) are injected under plasticizing conditions, and that the fed web segment (43) is simultaneously cut to the desired format of the plastic mat. 10. The method according to claim 9, characterized in that the high polymer materials A and B are selected so that they can form a common melt when heated under the injection conditions. 11. The method according to any one of claims 9 and 10, characterized in that for at least the underside of the mat and the suction cups, thermoplastic high-polymer materials are selected which are made from the same basic monomer type, preferably from the same monomer, even more preferably from a foamed high-polymer material A and a non-foamed high-polymer material B. exist, where A and B are the same polymers. 12. The method according to any one of claims 9 to 11, characterized in that PVC or a polyolefin, the latter preferably polypropylene, is used as the highly polymeric materials. 13. The method according to claim 12, characterized in that one uses soft PVC as high polymer material B, PVC foam film as high polymer material A. 14. The method according to claim 12, characterized in that a polyolefin, in particular polypropylene, optionally rubber-modified, as high polymer material A, and as high 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 6 11 CH 684 679 A5 polymeric material B uses a rubber-modified polyolefin, in particular polypropylene, particularly preferably PP / EPDM. 15. The method according to claim 9, characterized in that a primer is used to promote adhesion between the polymers at least the mat underside A and the suction cups B. 16. The method according to claim 15, characterized in that there is used as an adhesion promoter (primer) polyurethane or acrylate primer. 17. The method according to any one of claims 9, 15 and 16, characterized in that the primer is already applied to the web material which is fed to the molding tool (4, 33) or immediately before the web material enters the molding tool (4, 33) is applied to the web goods. 18. The method according to any one of claims 9 to 17, characterized in that holes are provided in the mat for water flow or drainage. 19. The method according to any one of claims 9 to 18, characterized in that one additionally compresses the mat edges under pressure and heating. 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 7