DE2927360A1 - METHOD FOR PRODUCING UNDER DEFORMING IN A PRESS AT HIGH TEMPERATURE OF REINFORCED POLYURETHANE MOLDING FOAM PANELS AND PLATES PRODUCED BY THE PROCESS - Google Patents

Description

Patent attorneys

Dipl.-Ing. H. Schmitt

Dipl.-Ing. W. Mauchef

Drei "cninstraße 13

7 :: C-- ^ r iburg

f iJnserä Akfe- ^. Please always specify!

ROTH FRERES, S.A.

5, rue Schertz, STRASBOURG-MEINAU -Bas-Rhin-, France

Process for the production of reinforced polyurethane molded foam panels with deformation in a press at high temperature, as well as panels produced by means of the process

The present invention relates to manufacturing of molded panels, which are used in particular for suspended ceilings, for vehicle construction and the like, and has a manufacturing process for the subject, in which by deformation in a press at high temperature reinforced Polyurethane foam molded panels are produced.

The invention also relates to a means of Process manufactured plate.

Hard or semi-hard polyurethane foams are currently available available that have excellent thermoplastic properties have, so that a plate of such a foam is heated to soften and then between the

with .one
Plates a / die and a punch equipped press can be placed and after the complete cooling of the foam, the plate has a permanent shape. the

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Cooling down of the foam occurs quickly because it is during the compression takes place in the pressing tool that otherwise is preferably water-cooled.

The Plattpnraaterial for the production of the mold plates is either by cutting with the desired thickness of solidly eaten foam blocks or by producing foam in layers between two circumferential bands generated, the distance between them determines the thickness of the foam panels.

The polyurethane foam consists of two parts or components, namely:

Component 1: 100 parts by weight of polyether resin ₍ such as the

Desmophen 1O77 A sold by Bayer AG,

0.2 to 1 part by weight of trimerization activator for the formation of polyisocyanurate, such as activator 1026 sold by Bayer,
0.5 to 2 parts by weight of water,

Component 2: 230 parts by weight of methylphenyl diisocyanate,

such as, for example, the one sold by Bayer AG Desmodur 1844 or 44 V 2O.

But the cost price and the weight of the known plates are high. To produce an 8 mm

strong molded panel of 2 m, the stability of which gives it self-supporting properties, so that the panel can be used For the production of a car roof, the base plate must have a thickness of 40 mm and a density of 80 g / l. After forming and compressing to a thickness of

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2
8 mm with an area of 2 m, such a plate weighs 6.400 kg, so it is no longer a low-priced product.

The present invention is based on the object of eliminating these disadvantages.

For this purpose, the invention relates to a process for the production of reinforced polyurethane molded foam panels with deformation in a press at high temperature, which is characterized in that essentially a thin foam panel is provided on both sides with a reinforcing or stiffening film, the panel and / or the foils are coated with a bonding agent so that the plate and foils are placed in a heating cabinet or between two heating plates for one to two minutes at a temperature of 170 to 220 ° C, and then the resulting composite structure of removed from its heat source and placed between the plates of a press equipped with a punch and a die for a period of 3 to 10 seconds, on average 5 seconds, that the assembled structure is pressed for 30 seconds until it cools and that the press is used opens and takes out the final mold plate.

According to one feature of the invention, the connecting means is an irreversible polyurethane elastomer. which contains two polymerizable components.

According to yet another feature of the invention, the connecting means is used after it has been activated by the heat to lubricate the reinforcement foils along the foam board.

Also takes place according to a further feature of the invention

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a polymerization of the connecting agent even after the Melting by heating, with the · polymerization lasts another 48 hours, so that the process remains irreversible or irreversible, even if one exposing the mold plate to a temperature of 150 ° C.

According to one feature of the invention, this has the connecting means forming polyurethane elastomer preferably has the following composition:

Component 1: 100 parts by weight of one-component polyurethane such as the Dpsmocoll sold by Bayer AG or that by Witco sold Witcobond 524O;

Ingredient 2: 5 to 10 parts by weight isocyanate hardener, such as

E.g. the Witco XB sold by Witco.

The invention also relates to a mold plate produced by the method, characterized in that it essentially consists of a thin sheet of polyurethane foam, and from two reinforcement bzx. Stiffening foils on both sides using a connecting means in the form of irreversible polyurethane elastomers are connected to the plate.

For a better understanding of the invention there now follows the description of a preferred, given as an example, the scope of protection non-limiting embodiment with reference to the schematic drawings. Show it :

Figures 1 to 3 different phases of the invention

Manufacturing method and FIG. 4 shows a section through an inventive

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Plate.

A polyurethane foam sheet and / or two reinforcing or stiffening foils are first coated with a polyurethane elastomer, which consists of two components and is irreversible. For this purpose, the two components are mixed together in a vessel that is connected to a spray gun so that the polyurethane-elastomer mixture can be sprayed onto the plate and / or the stiffening foils. At ambient temperature, the drying of this mixture is complete within two or three hours, although drying is possible within a few minutes by hot air, infrared heating or the like or inside a heating cabinet.

As can be seen from FIG. 1, the foam sheet 1 is covered on both sides with the two foils 2 in a sandwich-like manner, after which the structure is placed between two heating plates 3 or in a heating cabinet so that the temperature is increased to 170 to 220 ° C. After heating for 1 to 2 minutes, the foam softens and the elastomer coating becomes liquid, the polymerization then being initiated by the heat. The assembled structure is then removed from the heating plates or from the heating cabinet and placed between the two plates of a press equipped with a punch 4 and a die 5, the time interval between removal from the heating apparatus and introduction into the press 3 to 10 Seconds, on average 5 seconds. Shaping takes place in the press by drawing (FIG. 2).

The press is then closed and during the pulling process the stiffening sheets slide along the surface of the foam sheet without tearing, whereby they move without tension

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can cling to the entire shape of the plate because the liquid polyurethane elastomer acts as a lubricant (Figure 3). The formation lasts for 30 seconds kept under pressure between the plates of the press, this period of time being sufficient for the cooling to be achieved by a Water circulation within the punch 4 and the die 5 is supported. After cooling down the press opened to remove the mold plate 6, which has a permanent shape and great stability because the stiffening foils are very firmly connected to the foam sheet and because the elastomer formed after it has acted as a lubricant, binds the structure together in the hardened state.

After the plate 6 has been removed from the press, it lasts chemical process of polymerization for another 48 hours until it is complete and irreversible, so that, even if the plate is exposed to a temperature of 150 ° C, the elastomer does not become liquid again.

The stiffening foils 2 consist of paper, in particular Kraft paper, a glass fiber fleece, a non-woven one Fabric, a woven fabric or a laminate or the like.

The rigidity or stability of the mold plate 6 is generated by the foils 2, which are formed with the plate 1 be glued. During molding, the irreversible elastomer is melted by the heating to create a sliding movement of the foils 2 along the surfaces of the plate 1 during deep drawing, so that the foils 2 the changes assume in the profile of the foam, which are brought about by the pressing tool. With this corresponding There is no change in the shape of the foils, no tearing and no undesirable tensioning of the material.

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Using the invention it is therefore possible, for example, to

a self-supporting shaped plate with a size of 2 m and a weight of 1,500 kg from a starting foam board that is 15 mm thick and its density 5O g / l.

Obviously, the present invention is not to the example described and shown in the drawings is limited. Changes are possible, in particular relating to the composition of the connecting means, without therefore to leave the scope of the invention.

[VV. Mav.c-.her) patent attorney

9098847078

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Claims (6)

DIpI.-Ing. H. Schmitt f ,. ~ ~ | Dipl.-ing. W. Mauchef *: '"·'" '* - - «üte sluts nxr. ■? I! J Drci'.önigstrasse 13 j | 7C03 Freiburg ;; -PATbN TANSPRUC H "" E "1 ^" "* ~ · * -« »« - * «-» 1. A process for the production of reinforced polyurethane molded foam sheets with deformation in a press at high temperature characterized in that one essentially has a thin foam sheet on both sides a reinforcing or stiffening film provides, wherein the plate and / or the foils are coated with a bonding agent that the plate including foils in a heating cabinet or between two heating plates, for one to two minutes at a temperature of 170 to 220 ° C accommodates that one then removes the resulting composite structure from its heat source and in one Period of 3 to 10 seconds, on average 5 seconds, between the plates one with a stamp and one Die-equipped press lays that one is the compound Press the structure for 30 seconds until it cools down and that the press is opened and the final one Takes out mold plate. 2. The method according to claim 1, characterized in that the connecting means is an irreversible polyurethane elastomer that contains two polymerizable components. 3. The method according to any one of claims 1 and 2, characterized in that the connecting means, after being reactivated by the heat, serves to lubricate the reinforcing foils along the foam board and, after cooling, as a connection. 4. The method according to any one of claims 1 to 3, characterized in that the connecting means is an elastomer which polymerizes by heating after melting, the polymerization 48 hours after molding in such a way continues, so that the process cannot be reversed, even if the mold plate is later heated to 150 ° C 90988W07S * 2327360 is exposed. 5. The method according to any one of claims 1 to 4, characterized in that the irreversible connecting means has the following preferred composition: Component 1: 100 weight of steep one-component polyurethane such as the Desmocoll sold by Bayer AG or that by Witco sold Witcobond 524O; Component 2: 5 to 10 parts by weight isocyanate hardener, such as E.g. the Witco XB sold by Witco. 6. Mold plate according to the method of claim 1, characterized characterized in that it consists essentially of a thin plate made of polyurethane foam and two reinforcement and respectively. Stiffening foils on both sides using a Connection means in the form of irreversible polyurethane elastomers are connected to the plate. 909884/0769