WO2001098068A1

WO2001098068A1 - Compression mould and method for producing a compression mould

Info

Publication number: WO2001098068A1
Application number: PCT/EP2001/006838
Authority: WO
Inventors: Peter Göricke
Original assignee: Goericke Peter
Priority date: 2000-06-21
Filing date: 2001-06-18
Publication date: 2001-12-27
Also published as: DE10192501D2; AU7966501A

Abstract

The invention relates to a compression mould (1) for producing ceramic products from ductile materials, comprising a supporting tool element (2) provided with a pressing side (3), and a coating (5) which is applied to the pressing side (3) and which comprises a pressing contour (4). The aim of the invention is to produce a compression mould having a comparatively long shelf life on the one hand and whereby the tendency of the pressed material to adhere to the compression mould after being pressed is reduced on the other hand. In order to achieve this, the coating (5) is embodied as a composite material, having an outer layer (6) made of a plastic which is non-polar and/or independently non-adhesive and/or cannot be made permanently sticky; and a three-dimensional carrier matrix (7). The plastic is at least partially embedded in one side (8) of the carrier matrix and is thereby mechanically connected thereto (7). The carrier matrix (7) is also firmly connected on the other side (9) to the supporting tool element (2).

Description

Preßwer tool and method for producing a press tool

The invention relates to a pressing tool for producing ceramic products from kneadable materials, with a carrier tool part having a pressing side and a coating applied to the pressing side and having a pressing contour. Furthermore, the present invention relates to a method for producing a pressing tool for ceramic products from kneadable materials.

A press tool of the type mentioned and a method for producing such a press tool are already known from DD 245 395 AI. The known pressing tool has a carrier tool part, on the pressing side of which a coating of polyurethane is applied in order to be able to better absorb the forces occurring during the pressing.

Furthermore, from DE-AS 22 17 608 a plastic working mold for the industrial production of ceramic products from kneadable materials is known, which consists of porous polyurethane, the working surface of which has a pore structure.

Finally, GB-PS 1 355 521 also shows a pressing tool of the type mentioned at the outset, a coating of polyurethane being applied to the carrier tool part. This coating is intended to prevent the pressed material from sticking after pressing.

Although it is fundamentally advantageous to coat a carrier tool part, for example made of metal, on its pressing side with polyurethane in order to prevent the pressing material from sticking to the pressing tool after pressing, the pressing or sticking of the pressing material can also be done with an applied polyurethane coating do not rule out entirely. This has the consequence that the pressing process must be interrupted frequently in order to clean the pressing tool on its pressing side or on the pressing contour.

Due to the previously described disadvantages of the prior art, a coating is often dispensed with in practice and the classic pressing process drive using pressing tools in which the carrier tool part consists of plaster. Gypsum pressing tools have the advantage that the material to be pressed hardly adheres to the gypsum after pressing, since gypsum is capillary-porous and absorbs the water that occurs during pressing. The use of gypsum as the material of the carrier tool part has the further advantage that the carrier tool part breaks when rigid foreign bodies are enclosed between the pressing tools without damaging the presses. The disadvantages that arise in connection with the gypsum, such as a short service life and covering of the pressed material with an undesired calcium sulfate layer after a short time, are frequently accepted. Due to the short service life, frequent replacement of the pressing tools is required, which is associated with correspondingly high costs. Another major disadvantage is the business interruptions that are required due to the replacement.

The object of the present invention is now to provide a pressing tool of the type mentioned at the outset and a method for producing a pressing tool, which on the one hand is intended to ensure a comparatively long service life of the pressing tool and on the other hand the tendency for the pressing material to adhere to the pressing tool the pressing is reduced.

The previously specified and derived object is essentially achieved in a pressing tool of the type mentioned at the outset in that the coating is formed as a composite material with an outer layer made of a non-polar and / or independently non-adhesive and / or non-permanently adhesive plastic and a three-dimensional carrier matrix in which the plastic is at least partially embedded on one side of the carrier matrix and the plastic is mechanically connected to the carrier matrix due to the embedding, and that the carrier matrix is firmly connected to the carrier tool part on the other side.

According to the method, in a first alternative embodiment it is provided that the press contour of the press tool is formed by a layer of a pourable, in the sense of spreadable plastic, which, as previously stated, non-polar and / or independently not adhesive and / or non-permanently sticky is, on the layer of plastic before curing the Plastic a three-dimensional support matrix or the layer is applied to the support matrix, so that the plastic is at least partially embedded in the support matrix on the other side of the support matrix and is mechanically connected to the plastic after curing due to the embedding. In an alternative embodiment, the carrier matrix is first applied to the carrier tool part or is provided thereon, and then the plastic is at least partially embedded in the carrier matrix.

When the present invention came about, it was found that the reason for the adherence of the pressed products to the pressing tool after pressing, in particular in connection with a polyurethane coating, can be seen in the fact that polyurethane is a polar plastic. Polar plastics are either self-adhesive, but in any case they can be made permanently sticky with an adhesive. This has the advantage that this plastic can also be easily applied as a coating to a carrier tool part. This is not possible with a non-polar plastic such as silicone, polytetrafluoroethylene, polyethylene or polypropylene. In addition, due to the non-polarity of these plastics, there is no connection with the material to be pressed and therefore no adhesion of the pressed products to the pressing tool.

The use of non-polar plastics in connection with pressing tools has obviously not been considered so far, since a coating consisting of a non-polar plastic cannot be permanently connected to the carrier tool part.

However, the present invention is not limited to providing only the use of a non-polar plastic as a coating in connection with a pressing tool, since - as previously filled out - such a plastic cannot be permanently connected to the carrier tool part itself. In addition, the invention proposes the use of a three-dimensional carrier matrix in which the plastic is at least partially embedded on one side of the carrier matrix and the plastic is mechanically connected to the carrier matrix due to the embedding. The other side of the carrier matrix can then in turn be firmly connected to the carrier tool part. Embedding the plastic in the carrier matrix ultimately results in a solid mechanical one Composite in the form of a positive connection, with significantly better separation properties and longer service life compared to the known pressing tools.

In addition to the possibility of using a non-polar plastic in connection with a pressing tool for the first time in order to reduce the adhesion of the pressed products to the pressing tool, the use of the composite material from the plastic layer and the carrier matrix offers the possibility of influencing the properties of the coating , Depending on the type of carrier matrix, the thickness of the carrier matrix and the plastic layer and the depth of the embedding, different (strength) properties of the coating result.

In order not to have to fear a partial detachment of the coating from the carrier tool part during the pressing process, the carrier matrix is preferably connected to the carrier tool part over the entire surface. In addition, the plastic should also be applied to the entire surface of the carrier matrix in order to ensure good detachment of the material to be pressed from the pressing tool at every point of the pressing contour.

As has already been explained above, it is possible to change the properties of the coating as a composite material using a wide variety of parameters. This also means that either a rigid or a flexible material is used as the carrier matrix. Depending on the application, it may be advisable to use either a rigid or a flexible material. For the present application, a fabric, a fiber material, a pore-shaped material and / or a loop-shaped material is preferably used as the carrier matrix. The materials glass fiber, glass fabric, carbon, fiber fabric, kevlar fabric, tear-off fabric, textile fabric such as terry cloth or foam are particularly suitable. Ultimately, it is crucial that a type of three-dimensional grid with the largest possible surface is obtained, which allows good embedding, also on both sides, and thus a good mechanical bond or form fit.

In a particularly preferred embodiment of the present invention, the material of the carrier tool part is at least partially embedded in the carrier matrix, the carrier tool part being mechanical due to the embedding is connected to the carrier matrix. In this embodiment, gypsum, for example, can easily be used as the material of the carrier tool part, which is poured onto the side of the carrier matrix opposite the plastic. After the plaster and plastic have hardened, a firm bond of all materials results.

The use of gypsum as the material for the carrier tool part is still expedient for the present application, even if the capillarity of the gypsum is no longer used to absorb water from the pressed material, since the coating no longer permits water absorption. Nevertheless, the advantage of the plaster can be used that the carrier tool part breaks if there is hard, non-deformable material between the pressing tools. Damage to the presses can be avoided in this way.

Especially in connection with a pourable or flowable and hardening material for the carrier tool part, the use of a tool frame, into which the carrier matrix and the carrier tool part are introduced, is appropriate. In order to be able to guarantee a secure mounting of the carrier tool part and the coating in the tool frame, a form-fitting mounting is recommended. For this purpose, lateral openings can be provided in the tool frame, into which the material of the coating and / or the tool part flow and, after hardening, ensure a positive fit in the pressing direction.

Instead of using a pourable and hardening material for the carrier tool part, it is also possible to use a solid material for the carrier tool part. In this case, of course, the material of the carrier tool part cannot be embedded in the carrier matrix. The use of an adhesive connection is then appropriate for the firm connection of the support matrix and the support tool part. In contrast to the non-polar plastic, the carrier matrix can easily be glued to the pressing side of the carrier tool part, preferably over the entire surface, in order to be able to ensure the firm connection of the carrier matrix and thus the coating to the carrier tool part. Experiments have shown that, in particular, adhesives based on epoxy resins, polyurethane resins, unsaturated polyesters and / or polymetracylates are suitable as adhesives for the carrier matrix.

Furthermore, it has been found that the layer thickness of the carrier matrix depends on the material, but should in each case be greater than 0.2 mm. The penetration depth of the plastic and / or the adhesive should be greater than 0.1 mm, depending on the type and the layer thickness of the carrier matrix. The following layer thicknesses and subsequent penetration depths are particularly preferred for the materials mentioned above:

Material layer thickness in mm penetration depth in mm

Glass fiber 1.0 - ■ 4.0 0.5 - 2.0 G glass-fiber tissue beer 1 1,, 00 - - 33,, 00 0.3 - 1.0

Carbon fiber industry 0.5 - - 2.0 0.3 - 1.0

Kevlar fabric 0.5 - - 2.0 0.3 - 1.0

Tear-off fabric 1.0 - ■ 4.0 1.0 - 4.0 textile fabric 1.0 - - 3.0 0.5 - 2.0 S foam lining material 1 1,, 00 - - 44,, 00 1.0 - 4.0

Despite the above-mentioned preferred materials, layer thicknesses and penetration depths, it should be pointed out that in general any material that permits penetration of the plastic or the adhesive from both sides is to be regarded as suitable. Different parameters can be specified through different penetration depths and different materials. Is z. For example, if a simple glass fiber fabric is used that does not have a firm bond in itself, it is possible, after the plastic has been applied, by a suitable process such as spraying, dipping, rolling or the like and applying an epoxy resin on the back after the two plastics have hardened to separate them again by simply tearing the fiberglass fabric. If a terry cloth or a stable foam is used instead of the glass fiber fabric, it is not easily possible to separate the two materials again. Other parameters such as strength of the bond or penetration depth can also be influenced by certain material combinations. influence. Ultimately, the individual parameters must be coordinated for each application.

Further features of the present invention, in particular in connection with the manufacture of the pressing tool, result from the following description of exemplary embodiments with reference to the drawing. It shows

Fig. 1 is a schematic cross-sectional view of an inventive

pressing tool,

2 is a view corresponding to FIG. 1 of another embodiment of a press tool according to the invention,

3 shows a view corresponding to FIG. 1 of a further embodiment of a press tool according to the invention and

4 - 7 views of the different stages of manufacture of the press tool of FIG. 1st

1 to 3 each press tools 1 are shown, which are used to manufacture ceramic products from kneadable materials. Each of the pressing tools 1 has a carrier tool part 2, on the pressing side 3 of which a coating 5 having the pressing contour 4 of the pressing tool 1 is applied.

It is essential in all embodiments that the coating 5 is designed as a composite material and has at least two layers. An outer layer 6, which has the press contour 4, is provided, which consists of a non-polar and / or non-self-adhesive and / or non-permanent plastic. The plastic is preferably silicone, but other non-polar plastics such as fluoropolymers, polyethylene and / or polypropylene can also be used. Furthermore, the coating 5 has a three-dimensional carrier matrix 7 in addition to the layer 6. It is essential in this context that the plastic of the layer 6 on one side 8 of the carrier matrix is at least partially embedded in it, so that a mechanical connection in the manner of a positive connection between the layer 6 and the carrier matrix 7 due to the inclusion bedding results. Furthermore, the carrier matrix 7 is firmly connected to the carrier tool part 2 on the other side 9.

It is the case with all versions that the carrier matrix 7 is connected to the carrier tool part 2 over the entire surface, while the plastic embedded in the carrier matrix 7 is applied to the carrier matrix 7 over the entire surface. In the illustrated embodiments, a flexible fabric, namely in particular a terry cloth, is used as the carrier matrix 7, which is loop-shaped or loop-shaped on its two outer sides and is therefore particularly suitable for embedding on both sides. In principle, however, it is also possible, depending on the application, to use a rigid material or another flexible material for the carrier matrix. If appropriate, it also makes sense to design the carrier matrix in such a way that the plastic and thus the layer 6 can only be embedded in the carrier matrix 7 to a certain depth.

The embodiment of the pressing tool 1 according to the invention shown in FIG. 1 is characterized in that the material of the carrier tool part 2 is embedded in the transition to the carrier matrix 7, so that there is a mechanical connection between the carrier tool part 2 and the carrier matrix 7 due to the embedding , In the illustrated embodiment, the material of the carrier tool part 2 is plaster. It goes without saying that it is also possible in principle to use another pourable or flowable material which hardens after casting, for example a plastic.

Due to the use of a pourable or flowable, i.e. H. flowable and hardening material in the manufacture of the pressing tool, in the embodiment shown in FIG. 1, this has an outer peripheral tool frame 10, into which the carrier tool part 2 and the coating 5 are introduced and positively held therein.

Such a tool frame is not absolutely necessary in the embodiments shown in FIGS. 2 and 3. Here, the carrier tool part 2 consists of a solid material, in the present case of metal. The coating 5 composed of the layer 6 and the carrier matrix 7 is glued to the carrier tool part 2. For this purpose, an adhesive layer 11 is provided between the side 9 and the pressing side 3 of the carrier tool part 2, with which the support matrix 7 is glued to the support tool part 2 over the entire surface. In the present case, an epoxy resin serves as the adhesive for the adhesive layer 11.

Otherwise, the embodiments of FIGS. 2 and 3 differ in that the carrier tool part 2 in the embodiment according to FIG. 2 has an essentially flat press side 5. The press contour 4 in the layer 6 results exclusively from the shape of the layer 6. In this respect, the embodiment according to FIG. 2 is comparable to that according to FIG. 1. In the embodiment according to FIG. 3, the press contour 4 of the press tool 1 is at least essentially predetermined by the shape of the press side 3 of the carrier tool part 2. The coating 5 has essentially the same thickness over its surface. It goes without saying that such an embodiment can also be implemented in an embodiment as shown in principle in FIG. 1.

4 to 7, an inventive method for producing a pressing tool 1 is now shown. For this purpose, the tool frame 10 is first placed on a negative mold 12. The negative mold 12 has the negative press contour on its surface. The layer 6 is then applied to the negative mold 12 in the tool frame 10. The plastic is liquid in this state. Subsequently, the carrier matrix 7 is placed on the layer 6, before the plastic hardens. If necessary, the carrier matrix 7 is pressed into the still liquid plastic, so that the previously described embedding of the carrier matrix 7 results, as shown in FIG. 6. After the plastic has hardened, the space located above the carrier matrix 7 is poured out with plaster within the tool frame 10, so that there is also a positive fit between the plaster and the carrier matrix 7 by embedding the plaster in the carrier matrix 7. After the plaster has hardened, the pressing tool 1 is finished.

The pressing tools shown in FIGS. 2 and 3 are manufactured in a different way. There are different ways of doing this. In one alternative, the adhesive layer 11 is first applied to the pressing side 3 of the carrier tool part 2. The carrier matrix 7 is then glued to the carrier tool part 2. The layer 6 is then applied to the carrier matrix and the press contour 4 is produced. It is also possible for the carrier matrix to be glued to the carrier tool part 2 together with the plastic which already has the press contour.

In the embodiment shown in FIG. 3, the press contour 4 of the press tool 1 is already predetermined by the press side 3 of the carrier tool part. The coating is applied either by first gluing on the carrier matrix and then applying the plastic, or by applying the prefabricated composite material.

Claims

claims:

1. Press tool (1) for producing ceramic products from kneadable materials, with a carrier tool part (2) having a press side (3) and a coating (5) having a press contour (4) applied to the press side (3), characterized in that that the coating (5) is formed as a composite material with an outer layer (6) made of a non-polar and / or independently non-adhesive and / or non-permanent adhesive plastic and a three-dimensional carrier matrix (7), in which the plastic on one Side (8) of the carrier matrix (7) is at least partially embedded and the plastic is mechanically connected to the carrier matrix (7) due to the embedding, and that the carrier matrix (7) on the other side (9) is firmly connected to the carrier tool part (2) is.

2. Press tool according to claim 1, characterized in that the polymer used is silicone polymer, fluorine polymer, polyethylene and / or polypropylene and that, preferably, the plastic is applied to the entire surface of the carrier matrix (7).

3. Press tool according to claim 1 or 2, characterized in that the support matrix (7) is connected over the entire surface to the support tool part (2) that, preferably as a support matrix (7), a rigid or a flexible material is used and that, preferably, as Carrier matrix (7) is a fabric, a fiber material, a pore-shaped material and / or a loop-shaped material, in particular glass fiber, glass fabric, carbon fiber industry, Kevlar fabric, tear-off fabric, textile fabric such as terry cloth or foam.

4. Press tool according to one of the preceding claims, characterized in that the material of the carrier tool part (2) is at least partially embedded in the carrier matrix (7) and that the carrier matrix (7) is mechanically connected to the carrier tool part (2) due to the embedding and that, preferably that the support tool part (2) consists of a pourable and hardening material, in particular plaster.

5. Press tool according to one of the preceding claims, characterized in that the coating (5) and the carrier tool part (2) are introduced into a tool frame (10) that, preferably, the coating (5) and / or the carrier tool part (2) are positively held in the tool frame (10) and that, preferably, the carrier tool part (2) consists of a solid material such as metal, wood, ceramic, plastic and / or composite materials.

6. Press tool according to one of the preceding claims, characterized in that the carrier matrix (7) on the other side (9) with the pressing side (3) of the carrier tool part (2) is glued that, preferably, the carrier matrix (7) is glued over the entire surface to the carrier tool part (2) and that, preferably as an adhesive for the carrier matrix (7), adhesives based on epoxy resins, polyurethane resins, unsaturated polyesters and / or polymethacrylates are used.

7. Press tool according to one of the preceding claims, characterized in that the layer thickness of the carrier matrix (7) is greater than 0.2 mm depending on the material, and that, preferably, the depth of penetration of the plastic and / or the adhesive is greater than 0.1 mm.

8. A method for producing a press tool (1) for ceramic products from kneadable materials, the press contour (4) of the press tool (1) being formed by a layer (6) of a pourable or flowable plastic which is nonpolar and / or is not to be self-adhesive and / or not to be permanently sticky, a three-dimensional carrier matrix (7) or the layer (6) made of plastic being applied to the carrier matrix (7) on the plastic layer (6) before the plastic hardens, so that the plastic is at least partially embedded in the support matrix (7) on one side (8) of the support matrix (7) and is mechanically connected to the plastic due to the embedding after curing, and wherein after the plastic has hardened, the support matrix ( 7) on the other side (9) with a carrier tool part (2) is firmly connected.

9. The method according to claim 8, characterized in that the press contour (4) is produced on a negative mold (10) that, preferably, on the negative mold (12), a tool frame (10) is placed, into which the plastic is poured and the carrier matrix (7) is placed after casting, and that, preferably, after the plastic has hardened into the tool frame (10) directly on the carrier matrix ( 7) a pourable material is poured in.

10. A method for producing a pressing tool (1) for ceramic products from kneadable materials, wherein a three-dimensional carrier matrix (7) is applied to a carrier tool part (2) and wherein a layer (6) of a non-polar and / / or independently non-adhesive and / or permanently non-permanent plastic is applied in such a way that the plastic is at least partially embedded on one side (8) of the carrier matrix (7) and mechanically connected to the carrier matrix (7) due to the embedding.

11. The method according to claim 10, characterized in that the press contour (4) of the press tool (1) by the press side (3) of the carrier tool part (2) is predetermined, and that, preferably, the plastic is applied to the carrier matrix (7) without a surface treatment of the plastic is carried out.