DE3206468C2 - - Google Patents

Description

The invention relates to a method for manufacturing an interior trim panel for motor vehicles, especially automotive headlining, using a foaming, hard adjusted polyurethane mass, a soft polyurethane cut foam board and one visible top layer, these layers in one be deformed or react in a single pressing operation. The invention further relates to the use of a Glass fiber laid.

Such a method is described in DE 29 15 474 A1 described. There is a soft polyurethane Cut foam board is a rigid polyurethane foam upset. With the rigid foam, the top layer becomes glued. So this is not softly padded. By the rigid foam is intended to stiffen the Soft foam sheet can be reached. A stiffener it is not intended for the rigid polyurethane foam.

According to DE 30 22 017 A1 is used as a stiffening insert for a motor vehicle headlining a fleece made of synthetic fibers used. This can increase impact ability and reduce the risk of crumbling. There  the top layer is not soft cushioning soft foam layer provided. Did you want one to provide such, then there would be another Operation necessary.

DE 22 59 862 A1 describes an inner lining Polyethylene foam sheets on stiffening layers are upset. A can be used as a stiffening layer resin-impregnated glass fiber fleece may be provided. A Rigid polyurethane foam layer is not provided. To the Applying a top layer is a second Process step necessary.

The US-PS 36 47 588 gives an indication of hard and Soft foam, but again sets two process steps ahead. A foamed stiffening insert is not intended.

DE 31 16 432 A1 is also in a single step Shaped inner lining for motor vehicles described. Between a rigid sub-layer and a top layer, which are already available as finished layers, is one Barrier film provided.

As is known, for interior panels for Motor vehicles, especially motor vehicle headliners, high Intrinsic rigidity, lasting shape retention, low Weight, low height, handsome and soft padded top layer, easy to assemble and a low price demands. According to the state of the art only partially met these requirements. This is because remember that there are measures to meet the requirements oppose.

The object of the invention is a method of the beginning to propose the type mentioned, in which there is an intensified Hard foam layer and a soft foam layer with  Form the top layer in a single molding process and let press.

According to the invention, the above object is in a method of type mentioned solved in that the hard set polyurethane mass in a glass thread is foamed that between the hard set Polyurethane mass or the glass thread and the soft Polyurethane cut foam sheet a barrier film is inserted that on the soft polyurethane Cut foam board a soft, foamable Polyurethane mass is applied and that in the mold the glass fiber fabric as a whole and the polyurethane Cut foam board at least in some areas be squeezed together.

It is favorable that by a single pressing process the inner panel with reinforced Rigid foam layer and padded top layer in the desired shape is produced. It is not so further pressure to apply the upholstery and / or the top layer is necessary. Besides, is ensures that the layers in the Installed temperatures and Do not separate moisture.

It is also favorable that the glass fiber scrim is not included the polyurethane foam can react, but in this is only embedded mechanically. With this mechanical Embedding, the glass fiber scrim is pressed together - which improves the intimate embedding. However, it will not the glass fiber scrim in its main layers destroyed.

Such a glass fiber scrim is a preliminary product available. It is known on the market as a filter material. A such glass fiber scrim differs from one Glass fiber fleece, for example, in that the  Glass fiber scrim is made from continuous filaments. These are predominantly in the two directions of a plane (Main laying level) directed and interconnected, with several such main layers in comparison to Thread thickness very large distance are provided. Also in this way, glass fiber fabrics differ from Glass fiber fleeces and glass fiber mats.

Preferably, the glass fiber scrim is in the press mold inserted that its main laying levels parallel to Plate surface.

A manufactured by the method according to the invention Inner panel has low weight and low thickness a high inherent rigidity than Motor vehicle headlining, so that to the places of attachment on the vehicle roof neither on their number nor on their Size special requirements must be made. In addition, the interior trim panel can be used without further according to the, especially with one Motor vehicle headlining, two or produce three-dimensional shape requirements.

The inner panel is not deformable limited to the actual roof bend. It can also base for equipment elements of the roof and Edge beads part of the shape of the cladding panel be. The bottom of the interior trim panel is with a decorative top layer provided with a cushioning soft foam layer over polyurethane Soft foam is connected, which at the same time over the Barrier film a connection to the polyurethane Hard foam layer.

In a preferred embodiment of the invention, the Sectional foam board in sections by a corresponding shape of the mold more compressed than it will in other areas. Through this partial  It is possible through the compression Soft foam layer padding in individual Zones, for example on imitated seams or the mentioned bases or folding edges of the edge beads to drop out.

The barrier film prevents hard foam from entering the Soft foam layer penetrates.

In an embodiment of the invention is in the mold the side of the cut foam plate facing away from the Glass fiber laid a corrugated cardboard layer at least in the only slightly deformable areas or a that Final layer covering glass fiber laid, by foaming the hard set Polyurethane mass is connected to this. This will another stiffening of the interior trim panel and also an improvement in the manageability of the Cladding panel reached. A can be used as the final layer spun or needled fleece, a fabric, a Knitted fabrics or a film can be provided. This brings Although not a significant stiffener, it does cover it Glass threads of the glass thread scrim to the outside.

The polyurethane compositions mentioned can each Be two-component components that are applied by spraying will. However, this means that the Foaming process of the polyurethane masses practically immediately after the two components have been combined, that is begins before the glass fiber fabric and the polyurethane Soft foam layer are inserted into the mold. In preferred embodiment of the invention are Polyurethane masses prepolymers and the mold is heated, so that the frothing and curing process only in the mold takes place. Such a thing Foaming process is in DE-PS 16 69 786 described. This also reacts in this case Glass fiber scrim not with the polyurethane mass. Because the  the temperature required for foaming is far below the melting temperature of the glass threads. The in Initial state of the glass fiber fabric existing weak Fixation between the glass threads can be in the Release the pressing process. This is for the end product harmless, because the fixation of the glass threads by the foamed rigid polyurethane foam is taken over. The solution of the original fixation of the glass threads of the Glass fiber laid fabric can have a favorable effect, since in the Then press mold one of the desired shape appropriate orientation of the glass threads of the scrim arises, which is then held by the rigid foam. Significant breaks in the compressed and deformed Eggs are avoided.

The invention also relates to the Use of a glass fiber scrim with a Basis weight between 300 and 600 p / m² with a thickness between 50 and 70 mm, with the glass fiber as Stiffening inlay of the rigid polyurethane foam layer one also a layer of flexible polyurethane foam and an inner lining panel having a covering layer for motor vehicles, especially one Automotive sky, serves.

Embodiments of the invention result from the following description. In the drawing shows  

Fig. 1 shows schematically the stratification provided for a motor vehicle roof in the initial state before pressing and

Fig. 2 shows the motor vehicle roof in the ready-to-install state, schematically in section.

To form the motor vehicle Sky 1, a press is provided with a lower mold and an upper mold are provided. The lower shape is adapted to the desired contour of the side 2 of the sky 1 facing the motor vehicle roof. The upper shape is adapted to the side 3 facing the interior of the motor vehicle. Accordingly, the upper shape in its contour adapted to the shape of the roof of the motor vehicle has projections which correspond to bases for ceiling lights, grab handles or sun shields. Such a base 4 is shown in FIG. 2.

In the partial section of FIG. 1, for example a PVC film overlying a top layer 5. An open-pore, soft polyurethane cut foam sheet 6 lies above this. A soft-set polyurethane polymer pre-product (prepolymer) is applied to both of these together with a catalyst. The thickness of the cut foam plate 6 is, for example, 3 mm to 5 mm. A barrier layer film 7 is placed on the cut foam plate 6 . The also consists of polyurethane, because then due to the nature of the materials, good adhesion between the barrier film 7 and the polyurethane foam impregnating the cut foam plate 6 arises. The thickness of the barrier film 7 is 25 microns.

A glass fiber scrim 8 is placed on the barrier layer film 7 . The weight of the glass fiber scrim 8 is between 300 and 600 p / m², preferably 300 p / m². Its thickness is approximately 50 to 70 mm, preferably 50 mm, in the non-compressed state shown in FIG. 1. The glass thread scrim 8 consists of glass threads with a thread thickness of 15 μm. It is made of glass threads that are endlessly made. The threads are fixed to each other with a binder which is acrylic resin or the like.

A hard-set polyurethane polymer intermediate product is applied to both sides of the glass fiber scrim 8 together with a catalyst.

A double-sided corrugated cardboard 9 is placed on the glass fiber scrim 8 . The area sizes of the cut foam plate 6 and the glass fiber scrim 8 are approximately the same. The area of the corrugated cardboard 9 is smaller. It only extends over central areas that are not very deformable (see FIG. 2).

The stratification described is inserted into the heated press and pressed to the motor vehicle headlining 1 according to FIG. 2. During the pressing, the previously airy glass fiber scrim 8 is compressed to a thickness of 4 to 5 mm, preferably 5 mm. The soft foam layer formed by the cut foam plate 6 is less compressed. It is compressed more than in other areas in areas of base 4 .

The prepolymers then foam under the action of heat and, if appropriate, that of an activator. The threads of the glass thread 8 are foamed by hard foam. The glass fiber scrim 8 should be completely foamed through by the hard foam. The pores of the cut foam plate 6 are foamed through by the soft foam in more compressed zones. In less compressed zones of the cut foam plate 6 , the soft foam does not foam through the cut foam plate 6 , but remains in superficial border zones, so that a core remains free of soft foam in the interior of the cut foam plate 6 .

The hard foam of the glass fiber scrim 8 simultaneously forms a connection with the corrugated cardboard 9 and with the barrier film 7 . The polyurethane foam of the cut foam plate 6 likewise forms a connection with the barrier layer film 7 . In addition, it connects the cover layer 5 to the cut foam plate 6 .

After a short time, the polyurethane materials are cured, the polyurethane layer surrounding the glass fiber layer 8 and holding the corrugated cardboard 9 being harder due to its setting than the polyurethane layer which only penetrates the cut foam plate 6 in some areas and holds the cover layer 5 . The barrier film 7 prevents hard foam from penetrating into the cut foam plate 6 and hardening it undesirably.

In a further exemplary embodiment of the invention, a closed-pore polyurethane foam is used for the cut foam plate 6 . In this case the barrier layer is not necessary. Because the rigid foam cannot penetrate into the closed pores. There is then a direct connection between the rigid foam penetrating the glass fiber scrim 8 and the soft foam applied to the cut foam plate 6 . In this case, it may also be sufficient to provide the cut foam plate 6 with prepolymer only on the side facing the cover layer 5 , so that the rigid polyurethane foam then penetrates directly into the cut pores of the cut foam plate 6 and produces the desired connection.

It is possible to use corrugated cardboard only closed on one side as corrugated cardboard 9 . The rigid foam stiffens them. The corrugated cardboard 9 increases the buckling stiffness of the motor vehicle headliner 1 . In another exemplary embodiment of the invention, instead of the corrugated cardboard 9, an end layer extending over the entire glass fiber layer 8 is provided. Although this does not bring any significant stiffening, it covers the glass threads of the glass fiber layer 8 from the outside and, like the corrugated cardboard 9 , prevents the "bimetal effect" which, as is known, can lead to a warping of the motor vehicle headlining 1 with only one-sided lamination.

It is also possible to reinforce in particular Areas partially with a second layer of glass fiber scrim to provide.

In the shaping of Fig. 2 of the automotive roof 1 is compressed at its edges stronger than otherwise. In the middle axis of the headliner 1, a ridge 10 is formed which bypasses a spar of the vehicle roof or is only for decoration.

Overall, the invention provides a motor vehicle headlining which is free in terms of its shape, the top layer 5 of which is softly padded by the cut foam plate 6 , which is dimensionally stable and nevertheless occupies a low overall height. The motor vehicle headlining can be produced in a simple manner in the described method.

Claims (7)

1. A method for producing an interior trim panel for motor vehicles, in particular motor vehicle headlining, using a foaming, hard-set polyurethane composition, a soft polyurethane cut foam panel and a visible cover layer, these layers being deformed or reacting in a single pressing process, characterized in that the hard-set polyurethane mass is foamed into a glass thread scrim ( 8 ), that a barrier film ( 7 ) is inserted between the hard-set polyurethane mass or the glass thread scrim ( 8 ) and the soft polyurethane cut foam sheet ( 6 ), that on the soft polyurethane cut foam sheet ( 6 ) a soft, foamable polyurethane composition is applied and that the glass fiber scrim ( 8 ) as a whole and the polyurethane cut foam sheet ( 6 ) are pressed together at least in regions in the press mold. 2. The method according to claim 1, characterized in that the polyurethane cut foam plate ( 6 ) is densified in certain areas. 3. The method according to claim 1 or 2, characterized in that in the mold on the polyurethane foam sheet ( 6 ) facing away from the glass fiber layer ( 8 ) a corrugated cardboard layer ( 9 ) at least in the region to be deformed only slightly or one of the glass thread layer ( 8 ) covering final layer is placed, which is connected to this by foaming the rigid polyurethane foam. 4. The method according to any one of the preceding claims, characterized in that the polyurethane compositions Are prepolymers and the mold is heated so that the foaming and curing process in the mold takes place. 5. The method according to any one of the preceding claims, characterized in that the glass fiber scrim ( 8 ) is inserted into the mold so that its main laying planes are parallel to the plate surface. 6. The method according to any one of the preceding claims, characterized in that the glass filaments of the glass filament scrim ( 8 ) are held together by means of a foamed, hard-set polyurethane mass. 7. Using a glass fiber scrim with a Basis weight between 300 and 600 p / m² with a thickness between 50 and 70 mm, characterized in that the Glass fiber scrim as a stiffening insert of the Polyurethane rigid foam layer one more Polyurethane soft foam layer and a top layer having interior cladding panel for motor vehicles, especially of a motor vehicle sky.