AT398382B - Method of producing a plastic laminate especially suitable for ski construction, plastic laminate and use thereof - Google Patents

Abstract

Method of producing a plastic laminate especially suitable for ski construction, based on woven or laid fibres impregnated with a pressure-setting synthetic resin curing mixture, by pressing with embossing plates, a stack consisting of the separating sheets 2, 2', 2'', 2''' impregnated with the pressure-setting synthetic resin curing mixture, the woven or laid fibres 3, 3' and embossing plates 4, 4' being formed in the mould in a heatable press, the impregnated separating films 2, 2', 2'', 2''' resting against at least one side of the woven or laid fibres 3, 3' and the embossing plates 4, 4' resting against the impregnated separating films, this stack being pressed at a temperature of about 100 degree C, so that, as a result of the contact pressure of the embossing plates on the impregnated separating films, the pressure-setting synthetic resin curing mixture can penetrate into the woven or laid fibres, the surface of the woven or laid fibres simultaneously being provided with dimples 6, 6', 9, 9' corresponding to the shape of the embossing plates, and the stack subsequently being tempered for about 8 to 10 hours to cure the pressure- setting plastic resin and then being desized. This method is intended to solve the technical problem which arises with the known plastic laminates whose surface is entirely continuous and therefore difficult to foam.

Description

AT 398 382 B

The invention relates to a method for producing a plastic laminate, particularly suitable for ski construction, based on fiber fabric or scrim impregnated with a duromer synthetic resin / hardener mixture by pressing with stamping sheets, a plastic laminate produced by this method and its use in ski construction.

Pressing with embossed sheets is known, for example, from DE-OS-28 13 388, whereby a finish ski surface is produced which has decorative papers as the surface layer, which can be labeled and also embossed during pressing.

The production of a ski laminate of the type mentioned above is also known from AT-PS-349 366, according to which glass fiber strands are continuously impregnated with a resin-hardener mixture, for example based on an epoxy resin, and then passed through a calibration opening to form a wet strand. The epoxy resin-glass fiber laminate produced in this way is now cut to order lengths and sanded to improve the bondability. This plastic laminate is then pressed together with the aid of a hardening binder, for example one based on epoxy resin, with a thermoplastic film serving as a cover layer at a temperature of 60 to 80 ° C. for a period of 30 to 60 minutes while the binder is hardening. If the plastic laminate serves as a surface composite component, an ABS film is often used as the top layer; if it is used as a composite tread component, a polyethylene film serving as a sliding surface is used.

This process is now very complex and also leads to a plastic laminate, the structure of which is completely closed to slightly porous. This turned out to be disadvantageous if the plastic laminate is used for ski production according to the new reaction injection molding process. In this reaction injection molding process, a mold is designed with the ski components such as the upper and lower flange and the ski core, and a mass of low-viscosity PU elastomers is injected into the remaining cavities. This ski manufacturing process has now shown that plastic laminates with a consistently closed surface are difficult to foam.

The skis produced from these known plastic laminates by the reaction injection molding process are not resistant to temperature fluctuations in the snow, since the distance between the ski components and the ski core cannot be designed precisely and internal stresses in the material are thereby caused.

The invention is based on the object of specifying a method for producing a plastic laminate which is particularly suitable for this special ski construction, which on the one hand requires little work and on the other hand leads to a plastic laminate which, due to its surface properties, is used in the reaction injection molding process can.

The object on which the invention is based is achieved in the process according to the invention in that a stack is formed in a heatable press, consisting of the separating foils impregnated with the thermosetting synthetic resin-hardener mixture, from the fiber fabrics or layers and from embossed sheets in the form that the impregnated separating foils rest on at least one side of the fiber fabric or scrim and the embossed sheets lie on the impregnated separating foils, so that this stack is pressed at a temperature of approx. 100 ° C., so that the duromer synthetic resin is pressed onto the impregnated separating foils by pressing Hardener mixture can penetrate into the fiber fabric or scrim, while at the same time the surface of the fiber fabric or scrim is provided with cups according to the shape of the embossed sheets and that the stack is then tempered for about 8 to 10 hours to harden the thermosetting synthetic resin and then desized.

Advantageously, the thermosetting synthetic resins used are those based on epoxy resins or polyurethane resins, and those made of glass fibers, carbon fibers or aramid fibers are used as fiber fabrics or scrims. Such starting materials can be processed particularly well and, as an essential property of the process product, ensure its high mechanical strength.

In another advantageous embodiment of the invention, the method is characterized in that the surface of the plastic laminate is ground after the annealing to form open cells.

The invention finally relates to a plastic laminate produced by the method according to the invention, which is characterized in that the surface of the plastic laminate has closed or open cells.

Further advantages of the configuration of the plastic laminate according to the invention consist in the fact that the top and the bottom of the plastic laminate have closed cells or the top of the plastic laminate have open cells and the bottom have closed cells.

According to another advantageous embodiment of the invention, there is a distance of 15 to 20 mm between the cells and the height of the cells is 0.2 to 2 mm. 2nd

AT 398 382 B

The different designs of the cups and their arrangement on the top and bottom of the plastic laminate can be carried out with little expenditure on equipment, that is to say by exchanging the differently structured stamping sheets.

The plastic laminate produced by the method according to the invention can serve as a spacer between the ski core and the other ski components and the injected polyurethane foam matrix in ski production 5 according to the reaction injection molding process. Due to the structured, that is to say with cups, laminate surface, the spacer to the ski core can be designed exactly. Subsequently, an adhesive (for example made of low-viscosity PU elastomers) is injected into the cavities formed between the cups, which is regularly distributed between the spacer and the ski core, thereby creating a particularly stable connection between these ski components.

The invention is explained in more detail with reference to Figures 1 to 6 and an embodiment.

FIG. 1 shows a top view of a laminate produced by the method according to the invention with open cells, which are shown on a scale of 10: 1, as well as a vertical sectional view indicated by the line II-II.

Figure 2 shows a laminate produced by the method according to the invention with closed cells, which are shown on a scale of 10: 1, in a plan view and below a vertical sectional view indicated by the line II-II.

FIG. 3 shows a laminate produced by the method according to the invention with open cups 20 on the top and closed cups on the underside in a top view and below a sectional view indicated by the line II-II.

FIG. 4 shows a laminate produced by the method according to the invention with closed cups on the top and bottom in a top view and below a sectional view indicated by the line II-II. 25 FIG. 5 shows a stack consisting of the separating foils impregnated with thermosetting synthetic resins, of the fiber fabrics or - and the stamping sheets for the pressing process.

FIG. 6 shows the use of the plastic laminate produced by the method according to the invention in a torsion box.

A press stack consisting of a 30 impregnated separating film 2, a fiber fabric in the form of a glass fiber mat 3, a further impregnated separating film 2 ', an embossing plate 4, a further impregnated separating film 2', a further glass fiber mat 3 is placed on a rubber plate 1 in a heatable press ', a further impregnated separating film 2' ', an embossing plate 4' - whereby this stack structure can be repeated eight times, for example - formed and pressed at a temperature of approx. 100 ”C. By pressing the stamping sheets 4, 4 'onto the 35 separating foils 2 and 2' impregnated with, for example, epoxy resin, the epoxy resin can penetrate into the glass fiber mats 3, 3 ', the surface of the glass fiber mats corresponding to the shape of the stamping sheets, 4 4 'is formed so that wells are formed on the surface of the glass fiber mats. Subsequently, the curing of the thermosetting resin is annealed for 8-10 hours at 70 eC. Then the stack is desized. If these wells are to be open on their surface, the surface is ground after desizing. 40 An illustration of this plastic laminate 5 is shown in FIG. 1, the cups 6 — shown on a 10: 1 scale — having an opening 7 on their surface. The course of the glass fiber fabric or scrim 8 is visible in the section taken along the line II-II. The height d of the cells 6 is, for example, 0.5 mm. The distance D between the cups 6 is 20 mm, for example. 45 If the surface of the laminate is not sanded after the tempering step, wells with a closed shape are formed, which are shown in FIG. 2 on a scale of 10: 1. 2, the plastic laminate 5 'has closed cells 6'. The course of the glass fiber fabric or scrim 8 'is visible in the section _ taken along the line II-II. The height d 'of the cells 6' is, for example, 1 mm. The distance D 'of the cells 6' from one another is, for example, 20 mm. 50 The laminate shapes shown in FIGS. 1 and 2 are produced in that only one side of the glass fiber mat, for example 3 with separating film 2 'stacked thereon, is embossed on one side. However, if the embossing is carried out on both sides — for example on the glass fiber mat 3 ′ in a stacked structure — a structure is produced as shown in FIGS. 3 and 4.

According to FIG. 3, a plastic laminate 5 " shown, the open well 6 " on the top and 55 closed cups 9 on the underside, the opening 7 being produced by a grinding process after the pressing step. The cups 9 are - due to the pressing step with impregnating resin which penetrates from the separating films into the cavity of 9 - filled. The height d " or the well 6 " is, for example, 0.5 mm. From the sectional view along the line II-ll is the course of the 3rd

Claims (14)

AT 398 382 B glass fiber fabric or scrim 8 " visible. The distance D " the well 6 " from each other is, for example, 20 mm. FIG. 4 shows a plastic laminate 5 ’" shown the closed cup 6 ’" has closed cups 9 'on the top and on the underside, the cups 9' being filled with impregnating resin which penetrates into the cavity 9 'from the separating foils due to the pressing step. The height d " ' or di ’of the cells 6 '" is, for example, 0.5 mm. From the sectional view along the line II-ll, the course of the glass fiber fabric or scrim 8 '" visible. The distance D " ' the well 6 '" to each other is, for example, 20 mm. An embodiment of the plastic laminate according to FIG. 1, 2, 3 or 4 can now be used for the production of a ski by the reaction injection molding method, see the illustration of a torsion box according to FIG. 6. In the reaction injection molding method, this is used by the method according to the invention Component 10 produced, for example, as a spacer element between the ski core 11 and the upper flange 12, since, due to the process, a mass of a low-viscosity polyurethane elastomer 13 is injected into the space created between the laminate 10 and the upper flange 12. On the other hand, the laminate 10 prevents the injection compound from penetrating into the ski core 11. In addition, an elastomer fleece 14, the steel edges 15, 15 'and the tread 16 of the ski are sketched in the figure. 1. A process for producing a plastic laminate, particularly suitable for ski construction, based on fiber fabric impregnated with a thermosetting resin-hardener mixture or - occasionally by pressing with embossing plates, characterized in that in a heatable press a stack consisting of the with the thermosetting synthetic resin Separating foils impregnated with hardener mixture (2,2 ', 2 ", 2 "'), from the fiber fabrics or layers (3,3 ') and from embossing sheets (4,4') in the form that on at least one side of the Fiber fabric or scrim (3,3 ') the impregnated separating foils (2,2', 2 ", 2 ") and on the impregnated separating foils the embossing sheets (4,4 ') rest so that this stack at a temperature of approx. 100Ό is pressed, so that the duromer synthetic resin-hardener mixture can penetrate into the fiber fabric or scrim by pressing the embossing sheets onto the impregnated separating foils, the surface of the F Aster fabric or scrim is provided with cups (6, 6 ') in accordance with the shape of the embossed sheets and that the stack is then annealed for about 8 to 10 hours to harden the thermosetting synthetic resin and then desized. 2. The method according to claim 1, characterized in that the thermosetting synthetic resin is one based on an epoxy resin. 3. The method according to claim 1, characterized in that the thermosetting resin is one based on a polyurethane resin. 4. The method according to any one of claims 1 to 3, characterized in that the fiber fabric or laid consists of glass fibers. 5. The method according to any one of claims 1 to 3, characterized in that the fiber fabric or scrim consists of carbon fibers. 6. The method according to any one of claims 1 to 3, characterized in that the fiber fabric or scrim consists of aramid fibers. 7. The method according to any one of claims 1 to 6, characterized in that the surface of the plastic laminate is ground after annealing to form open cells (6). 8. Plastic laminate produced by a method according to one of claims 1 to 6, characterized in that the surface of the plastic laminate has closed cells (6 '). 9. plastic laminate produced by a method according to any one of claims 1 to 6, characterized in that the plastic laminate has on its top and bottom closed cups (6 '", 9'). 4 AT 398 382 B 10. Plastic laminate produced by a method according to any one of claims 1- 7, characterized in that the surface of the plastic laminate has open cells (6). 11. Plastic laminate produced by a method according to any one of claims 1- 7, characterized 5 in that the top of the plastic laminate has open cells (6 ") and the underside of closed cells (9). 12. Plastic laminate according to one of claims 8 to 11, characterized in that there is a distance (D, D \ D ", D " ') of 15 to 20 mm between the wells. 10th 13. Plastic laminate according to one of claims 8 to 10, characterized in that the height (d, d ,, d ", d " ,, di, di ’) of the cells is 0.2 to 2 mm. 14. Use of a plastic laminate according to one of claims 8 to 13, characterized in that the plastic laminate is used for ski manufacture by the reaction injection molding method. With 3 sheets of drawings 20 25 30 35 40 45 50 5 55