EP2493684A1

EP2493684A1 - Method for producing a pressure plate, method for producing a pressure plate arrangement, and pressure plate arrangement

Info

Publication number: EP2493684A1
Application number: EP10770792A
Authority: EP
Inventors: Robert David; Gerhard Hochstein
Original assignee: OKT Germany GmbH
Current assignee: Keeeper GmbH
Priority date: 2009-10-29
Filing date: 2010-10-15
Publication date: 2012-09-05
Also published as: DE102009051311A1; WO2011051116A1

Abstract

The invention relates to a method for producing a pressure plate, in particular for use in short-cycle presses for producing directly coated flat boards, characterized by the following method steps: a) deforming a flat pressure plate blank (1a) into a hollow cylindrical or at least sectionally hollow cylindrical pressure plate blank (1b); b) placing the hollow cylindrical pressure plate blank (1b) on a carrier tool (5); c) structuring at least one portion of the surface of the hollow cylindrical pressure plate blank (1b) during the rotation of the carrier tool (5); d) removing the hollow cylindrical pressure plate (1c) having a structure (4) from the carrier tool (5); e) restoring the hollow pressure plate (1c) to a flat pressure plate (1) by deforming, and to a method for producing a pressure plate arrangement, in particular for use in short cycle presses for producing directly coated boards, wherein a pressure plate (1) produced according to one of the claims 1 through 9 is placed on a carrier plate (3), in particular glued thereto, and to a pressure plate arrangement for producing surface structures on flat plates, wherein the pressure plate arrangement comprises a pressure plate (1) and a carrier plate (3), wherein the pressure plate (1) has a structure (4) suitable as a positive part for applying structures on the flat boards, in particular in short cycle presses for producing directly coated wood materials, wherein the carrier plate (3) is connected to the pressure plate (1).

Description

description

METHOD FOR THE PRODUCTION OF A PRESSING PLATE, METHOD FOR THE PRODUCTION OF THE PRESS

MANUFACTURE OF A PRESS PLATE ARRANGEMENT AND PRESS PLATE ARRANGEMENT "

The present invention relates to a process for the preparation of a

Press sheet according to claim 1, a method for producing a press plate assembly according to claim 10 and a

Press plate arrangement according to claim 1 1.

In the manufacture of wood-based surfaces pressing plates are used as a structuring tools. Both in continuous operation (CPL / press belts) and in pulsed discontinuous operation (short cycle, high-pressure laminates), the press plates /

Endless belts as a patrix, a structure that is transferred during the pressing process in the resin surface of the wood material as a template. By means of heated, mostly hydraulic presses, heat and pressure are transferred to the surface of decor papers impregnated with aminoplastic or similar resins; the resins flow for a short time, then cure via polycondensation and in this process take on the structure of the press plate. This forms the final

Surface structure of the wood material.

A method for the production of press plates has become known for example from DE 40 33 230 C2. Here, on the one hand, a method for producing steel strips with a structure, that is a

Embossing engraving described in a continuous working

Heating press are used. On the other hand, a method for the production of press plates is sketched, which in a sequential

working heating press can be used.

The method according to DE 40 33 230 C2 has in common that the

Structuring of the surface is carried out by multi-stage chemical etching processes. In the examples according to DE 40 33 230 C2, laser beams act on a full-surface carrier web of plastic, elastomer or on a galvanic metal layer, which cover the press plate and / or the endless belt. The laser beams are in Controlled their intensity so that the structure produced by the laser beams detected only the thickness of the carrier web or the carrier layer, ie, the carrier web or the cover layer is structured in thickness only to the extent bare metal spots of the surface of the press plate or the endless belt exposed be so that subsequently the subsequent etching treatment can be made.

However, differences exist with regard to the movement of the steel strips or press plates in the structuring. While the endless belt is essentially spanned between two rotating rollers, the press plate is not moved during structuring by the laser. Rather, the laser - like a plotter - moves over the press plate.

It is intuitively obvious that the production of the press plate a

takes a considerable amount of time. The laser device often has to be accelerated and decelerated. Even if a structuring is carried out on the return trip of the laser, no short production times for the press plate can be achieved. In addition, the process steps laser exposure, etching and cleaning usually have to be repeated several times.

Although the press plates have a high mechanical life and hold several thousand cycles, press plates are one

Subjected to wear. Numerous parameters in the process, in particular abrasive materials such as corundum or TiO2 from the

Surface materials, cause wear of the press plates. Despite today already achievable long service life of the press plates are often structurally identical press plates nachfertertigen. Therefore, the

Reproducibility of the surface and structure in reproduction of a press plate is an essential quality criterion. Furthermore, the press plates are relatively expensive.

Press plates are usually chrome plated. Since the sheets can be quite large (up to 2.5 mx 6 m), comparatively large systems for chrome plating are necessary. In addition, the uniform chrome plating of such large press plates is technically very difficult and associated with high costs. Also for the new production of press plates, the time component plays an essential role. A short-term market introduction of new structures in the surface of wood-based materials is becoming an increasingly important success criterion for the economic success of a new one

Product development. The development and production times for

Press plates according to previous methods usually amount to several months to one year.

This is where the present invention is based, and it is an object to shorten the time for producing a press plate.

[001] According to the invention this object is achieved by a manufacturing method with the characterizing method steps of claim 1. The fact that the actual structuring is carried out on the press plate in a rotary process, can significantly higher

Process speeds can be realized. In this respect, press plates can be made much faster and cost and

Market advantages are achieved. The prior art methods, on the other hand, have the aim of producing flat press plates whose base material is usually tempered steels in a size of several square meters continuously in non-rotary working steps.

In an advantageous embodiment of the method, the

Surface structure in a direct Ablationsverfahren, preferably in a Ablationsverfahren using one or more laser ablated. In this way, the advantageous embodiment of the method according to the invention further differs from the prior art, in which the structuring of the surface usually takes place by multi-stage chemical etching processes. A corresponding

Method is described for example in DE 40 33 230 C2. Direct ablation procedures e.g. by means of laser beams are not known for the designated purpose. However, especially by comparison with the abovementioned chemical etching processes, considerable advantages are achieved, in particular by the direct ablation method, since the production of such large areas in flat methods has the required properties

Accuracy is a particular challenge. The occurring problems, for example, the registry of the

successively applied Ätzresistschichten for

Multi-stage etching before the respective etching as well as the

Difficulties in flat plating can be avoided by direct ablation. The laser ablation achieves a more exact mapping of the structure stored in the data record. The etch resist and the etching process eliminate two significant variables that are less well and accurately controlled than direct ablation by laser beams. The image quality and dimensional accuracy of the structure increases. The reproducibility of the surface with repeated production of the structure / the press plate increases. The creative possibilities increase, since it is possible to work directly from data records that can be transferred to the sheets with a higher accuracy and resolution, since the variables etching and etching resist are eliminated. The production times are reduced. In the conventional methods, the process steps are repeated. Applying etching resist / laser imaging. Etching resist /

Wash out etching resist / etching / cleaning several times. For the

Laser ablation, the sheet is once clamped in the laser machine. The reject rate decreases because the more accurate mapping of the

desired structure from the record and fewer deviations in the repeated production of known structures, the number of misfires is lower compared to the known methods. There is a legitimate assumption that laser ablation allows significantly enhanced design options for surface design. Environment and resources are less burdened because no chemical processes are necessary for direct structuring.

In a particularly advantageous embodiment of the method according to the invention it is provided that the aftertreatment of the press plate to increase the service life in particular by chrome plating the surface or by plasma ion implantation takes place while the press plate is on the on the carrier tool. It is well known in the art to chrome the surface of cylindrical bodies by immersing the bodies in a galvanic chrome bath and drawing a current Chromium ions are conducted to the surface of the body. The cylinder rotates at least partially in the chrome bath. With this technique, the pressure plate clamped on the carrier tool can also be chromed. The carrier tool including press plate is at least partially immersed in a galvanic chrome bath and rotated therein. The thickness of the chromium layer is then controlled by the amount of current.

Chromium wheels for chrome-plating cylindrical bodies are relatively compact and the application of a chromium layer is very precisely controlled and also inexpensive.

Another object of the present invention is to propose a method for producing a press plate assembly, with the facilitated production of a press plate assembly is made possible.

According to the invention the object is achieved in that the pressed sheet produced by means of the manufacturing method according to the invention applied to a support plate, in particular the press plate is glued to a support plate. In the production method known from the prior art, all processes on one-piece sheets

performed. Accordingly, the prior art press sheet is not a compound, that is, not a multi-layered structure. In essence, prior art press plates also have a final strength. In contrast, in the method of rotative press plate production described here, an originally flat press plate of thin thickness can first be pre-bent, structured in a round state and, if necessary, treated / finished, then returned to an approximately flat shape

bent back and glued to a carrier sheet to

sufficient mechanical strength and the final thickness to achieve. As a result, the press plate can be made substantially thinner, which in turn results in advantages for the manufacturing process. The forming and re-forming can be done much less problematic. The actual rigidity of the press plate is ensured by the support plate. Basically, that comes

Press plate arrangement but also without the carrier plate. In this Case, the press plate assembly is formed only from the press plate.

Another object of the present invention is to provide a

Press plate arrangement to propose, which has an advantageous stability, is inexpensive to produce and at least partially

is recyclable.

According to the invention this object is achieved by a press plate assembly according to claim 1 1. Because of that

Press plate arrangement is a so-called compound, a more advantageous coordination of the components of the press plate assembly can be made to the respective tasks. The press plate may for example be made thin, which may be expensive material can be saved. Furthermore, a comparatively thin press plate can be produced more advantageously by the method according to the invention. The material of the carrier sheet does not necessarily have to be of high quality, in particular it does not have to have the ablation properties of the press sheet. Rather, it can be on a low-cost carrier sheet

be used, which in particular has only the necessary stability properties. In addition, the carrier plate can also be separated from the press plate. The support plate and possibly also the press plate can be reused accordingly.

Further features and advantages of the present invention will be

clearly with reference to the following description

Embodiments with reference to the accompanying

Illustrations. Show in it

Fig. 1 is a schematic representation of a preferred

Production process for an inventive press plate and

Press plate assembly;

FIG. 2 is a perspective view of a flat press plate blank; FIG.

Fig. 3 is a perspective view of a hollow cylinder

shaped pressed sheet blank;

FIG. 4 is a perspective view of a vacuum cylinder with a hollow cylindrical press plate blank; FIG.

Fig. 5 is a perspective view of a vacuum cylinder with a hollow cylindrical and structured press plate;

Fig. 6 is a perspective view of a structured press plate which has been converted from the hollow cylinder shape back to the flat shape;

FIG. 7 shows a press plate arrangement according to the invention in one

Sectional view.

The following reference numerals are used in the figures:

1 press plate (with structure)

1 a pressed sheet blank

1 b pressed sheet blank in hollow cylindrical form

1 c pressed sheet in hollow cylindrical form with structure

2 adhesive layer

3 carrier sheet

4 structure

5 carrier tool / vacuum cylinder

6 lasers

7 seam

First, reference is made to FIG. 7.

In Fig. 7 is a schematic cross section through a

inventive press plate arrangement shown. A

The press plate arrangement according to the invention essentially comprises a press plate 1, an adhesive layer 2 and a carrier plate 3. The press plate 1 has a structure 4 which is suitable for applying structures to wood-based materials, in particular in short-cycle presses for the production of directly coated wood-based materials.

As the press sheet 1 for the press plate assembly, a thin sheet of stainless steel is preferably used (alloys, for example, DIN short name X15Cr13, X20CrMo13, X5CrNiCuNb17-4). Also conceivable are aluminum,

Non-ferrous metals, e.g. Nickel, zinc, copper (eg CuZn36 (Ms64)). Also conceivable are fiber composites, e.g. aftertreated

high heat resistant carbon fiber composites. Ultimately, all materials are suitable for this, which are suitable for laser ablation. The press sheet 1 should preferably have a thickness of 0.3 mm to 3 mm, especially preferably 0.5 mm. The structure depth is freely selectable and is preferably between 5 μηη and 250 μηη, more preferably between 10 μηη and 150 μηη.

The inventive method for the production of press plates

is characterized essentially by the fact that the structuring of the press plate takes place rotationally and clamped on a carrier tool and that provided with a structure, but still

hollow cylindrical or at least hollow cylindrical section-shaped

Press plate straightened in a subsequent process step, i.

is formed so that it takes the form of a conventional flat press plate. In other words, the structuring of the sheet metal surface takes place in a rotary and therefore very fast process step. The subsequent forming produced from the hollow cylindrical and provided with a structure press plate, a conventional flat press plate. In this respect, a press plate can be produced in a much shorter time.

The inventive method preferably comprises ten

Method steps, which are shown schematically in a brief description in the flowchart of FIG. 1 and will be explained in more detail below. Furthermore, selected manufacturing stages of the press plate or the press plate arrangement are schematically sketched in FIGS. 2 to 7.

1. Transformation of the press plate blank

In a first process step, the forming of a flat

Press plate blanks 1a in a hollow cylindrical press plate blank 1 b. A thin stainless steel sheet, preferably slightly oversized to the final die format, is pre-bent on a round blank or other suitable technology. The diameter of the resulting hollow cylindrical press plate blank should be about the diameter of the likewise preferably cylindrical

Carrier tool correspond, as will be described in more detail in the next step.

2. Clamping the deformed press plate blank In a second method step, a clamping of the

hollow cylindrical press plate blank 1 b on a carrier tool 5. Preferably, the pre-bent press plate blank 1 b is mounted on a vacuum cylinder 5. Alternatively, the press plate blank can also be clamped on another suitable cylindrical body as a carrier tool and welded at the seam. To

Completion of the press plate, the weld is separated and the press plate blank removed from the carrier tool.

It should be noted that the press plate blank is preferably the shape

a hollow cylinder should have a circular cross section and insofar the carrier tool, in particular the vacuum cylinder, can enclose. However, it is also conceivable that the

Press plate blank encloses only a part of the carrier tool. In this case, the press plate blank has the shape of a portion of a hollow cylinder. In this way, for example, several press plate blanks can be mounted on a carrier tool. It is of course also conceivable that two or more

hollow cylindrical press plate blanks side by side on a

Carrier tool are arranged. In essence, the shape of the press plate blank and the carrier tool is specified by the fact that the above components are set in rotation and the

Press plate blank must be reached by the laser beam. In this respect, it can be assumed for the rule of a circular cylindrical carrier tool and a corresponding hollow cylindrical press plate blank with a circular cross-section.

3. Structure on the surface of the press plate blank

In a third process step, the structuring takes place

at least part of the surface of the hollow cylindrical

Press plate blanks 1 b by ablation, accordingly by removal of material by heating. As a preferred method, ablation by means of laser 6 is possible here, but alternative treatments, such as electron beam ablation or ion beam ablation, are also conceivable. The spanned on the carrier tool 5 Press plate blank 1 b is installed in a laser device with sufficient laser power and set in rotation (indicated by the axis of rotation and the direction of rotation indicated). Depending on the desired structure depth, the excess material is removed in one or more passes from the laser. As a result, from the hollow cylindrical press plate blank 1 b provided with a structure 4 hollow cylindrical press plate 1 c.

The structuring on the surface preferably takes place completely digitally from a data record, data which is preferably spatially and height-resolved being used to control the laser 6. The surface is directly ablatively patterned by laser beams or other suitable ablation method (no etching after application of etch resist). The structure is rotational and clamped on a carrier tool (no processing of flat sheets). The structuring is also free of chemicals.

Depending on the desired structure and structure depth several passes are possible on the laser machine, wherein the laser beam in each

Passage is guided along the cylinder axis of the carrier tool, while the carrier tool rotates about this axis. After every

Passage should be a cleaning process take place, d. H. burn off at the lasered spots should be removed. This can be done by

mechanical processing, e.g. Brushes, by alternative methods such. Dry ice irradiation or any other suitable method. The cleaning is preferably carried out inline in the laser machine, in particular in order to keep the process times short. However, cleaning can also be done in separate machines.

4. Polish the surface

In a fourth step, a polishing process should take place, in particular, should the surface of the press plate 1 c, in which no structure has been introduced, polished after completion of the ablation and cleaning process depending on the desired degree of gloss or desired structure to shine or be reworked in the desired matt or structural degree. The latter can through mechanical processing, eg by grinding, brushing, sand blasting or by laser ablation.

5. Aftertreatment of the surface

In a fifth process step, a post-treatment of the

hollow cylindrical and now provided with a structure

Press plate 1c, which substantially the protection of the surface against those occurring in the production of wood materials

Stresses serves to be made. Preferably, here a chromium plating of the surface, alternatively a treatment by means of plasma ion implantation or other methods is carried out, which increases the mechanical resistance of the surface against the stresses in the manufacturing / coating process of

Wood materials guaranteed.

[0055] 6. Separation of press plate and carrier tool

In a sixth method step, the hollow cylindrical, provided with the desired structure press plate 1 c is removed from the carrier tool 5.

7. Re-forming the press plate

In a seventh method step, a reverse transformation of the

hollow cylindrical and structured press plate 1 c in a flat shape. This can be done for example in a suitable press. The result of the fifth method step is thus a structured and flat press plate 1.

8. Preparation for connection of press plate and carrier plate

In an eighth process step, a preparation for the

Joining the structured and flat press plate 1 done with the support plate 3. For this purpose, the press plate 1 on the back with a suitable adhesive system, preferably with a

thermoreactive adhesive based on silicone or other suitable adhesive systems, coated. Alternatively, a coating of the support plate 3, to which the press plate 1 is adhered, carried out with one of the aforementioned adhesive systems.

9. Connection between press plate and carrier plate In a ninth process step, bonding of press plate 1 and carrier plate 3 takes place in a flat press, a continuous press or by means of other suitable methods. As a result, a press plate arrangement according to the invention has now arisen, which is not configured in one piece but as a compound.

10. Post-processing of the edges of the press plate

In a tenth method step, a post-processing of the

Edges of the press plate.

[0065] 1. Workup Press Plate

After the use or the wear of the press plate - in a sense as conceivable eleventh method step - a redetachment of the press plate 1 from the support plate 3 can be made. at

thermoreactive adhesives, this is done by heating. In this respect, a reuse of the carrier sheet is conceivable, while for the

Press plate basically a new production is provided.

It should also be noted that the structuring and the polishing of the surface (third and fourth method step), as well as the

After treatment of the surface (fifth step) takes place on the carrier tool. It should also be noted that the press plate 1 can already be used as such, i. without being applied to a support plate 3. For this purpose, a suitable selection of the thickness and / or the material of the press plate 1 would have to be made and a press be equipped with a suitable receptacle.

By the proposed method according to the invention, a

technically and economically optimized production of

Press plates or Pressblechanordnungen for the production of

Surfaces are provided by, for example, wood materials. The press plates or Pressblechanordnungen are particularly suitable for use in short-cycle presses for surface coating in all laboratory and production formats (up to 2.5m x 6 m) for the production of directly coated wood materials (eg chipboard / MDF / HDF / other support). The press plates or press plate arrangements are also suitable for pressing and structuring high-pressure laminates (HPL / CPL), for lamination and structuring of thermoplastic films and finish foils based on preimpregnated papers

Wood materials of all kinds. Ultimately, the press plates or press plate assemblies according to the invention are suitable for all other applications in which structuring press plates in

discontinuous flat pressing process for structuring

Surfaces are needed.

With the method for the production of press plates or

Press plate arrangements, the time for the production of a new press plate, or a new structure, from the presence of a digital file can be significantly shortened.

Although the proposed press plate assembly is intended essentially for use in presses for the production of wood-based surfaces, so their use for other applications, such as circuit board manufacturing, conceivable.

Claims

claims

1. A process for the production of a press plate, in particular for use in short-cycle presses for the production of directly coated flat plates, with at least the following process steps:

a) forming a flat pressed sheet blank (1 a) in one

hollow cylindrical or at least hollow cylinder section-shaped

Pressed sheet blank (1 b);

b) applying the hollow cylindrical press plate blank (1 b) to a carrier tool (5);

c) structuring on at least a part of the surface of the

hollow cylindrical press plate blank (1 b) during rotation of the carrier tool (5);

d) removing the provided with a structure (4) and hollow cylindrical pressing plate (1 c) of the carrier tool (5);

e) reshaping the hollow cylindrical press plate (1 c) in a flat press plate (1).

2. The method according to claim 1, characterized in that it is the carrier tool (5) is a vacuum cylinder or another suitable cylindrical body.

3. The method according to at least one of the preceding claims, characterized in that the structuring on the surface of the

Press plate blanks by ablation, in particular by ablation with a laser (6) is made.

4. The method according to at least one of the preceding claims, characterized in that the structuring of the surface is completely digital from a data set, wherein as data preferably location and height resolved data for driving the laser (6) are used.

5. The method according to at least one of the preceding claims, characterized in that the structuring of the surface takes place in one or more passes.

6. The method according to at least one of the preceding claims, characterized in that a cleaning of the surface of the press plate blank (1 b, 1 c) is carried out, in particular by the ablation arising burn-off by brushing or dry ice irradiation is removed.

7. The method according to at least one of the preceding claims, characterized in that where no structuring has taken place, a polishing of the surface of the press plate (1 c) is made or post-processed in the desired matte or structural degree.

8. The method according to at least one of the preceding claims, characterized in that an aftertreatment of the press plate (1c) for

Increasing the service life is made in particular by chrome plating the surface or by plasma ion implantation.

9. The method according to at least one of the preceding claims, characterized in that the aftertreatment of the press plate to increase the service life in particular by chrome plating the surface or by plasma ion implantation takes place while the press plate (1 b, 1 c) on the on the support tool ( 5) is located.

10. A process for the production of a press plate assembly, in particular for use in short-cycle presses for the production of directly coated flat plates, wherein one prepared according to one of claims 1 to 9

Press plate (1) applied to a support plate (3), in particular glued to this.

1 1. Press plate assembly for the production of surface structures on flat plates, wherein

- The press plate assembly comprises a press plate (1) and a carrier plate (3), wherein

- The press plate (1) is provided with a structure (4) as a patrice for applying structures on the flat plates, in particular in

Short cycle presses for the production of directly coated wood materials, is suitable, wherein

- The support plate (3) with the press plate (1) is connected.

12. Press plate arrangement according to claim 1 1, characterized in that the press plate (1) at least partially made of stainless steel, aluminum,

Non-ferrous metal, in particular nickel, zinc, copper, or from a

Fiber composite material, in particular a post-treated

high-temperature carbon fiber composite.

13. Press plate arrangement according to at least one of the preceding

Claims, characterized in that the press plate (1) has a thickness of 0.3 mm to 3 mm, particularly preferably 0.5 mm.

14. Press plate arrangement according to at least one of the preceding

Claims, characterized in that an adhesive layer (2),

preferably a thermo-active adhesive based on silicone, for connecting carrier plate (3) and press plate (1) is provided.

15. Press plate arrangement according to at least one of the preceding

Claims, characterized in that the press plate assembly is made by the method according to claim 10.