EP1944141A2 - Method for manufacturing seat shells - Google Patents

Abstract

The method involves gluing the several layers of the seat shell together using pressure and heat. It involves providing at least one of the two outer layers of the seat shell with flocking on the exterior surface prior to gluing to the other layers over at least part of its surface while still flat.

Description

TECHNICAL AREA

The present invention relates to a method for producing curved, multi-layered seat shells, in particular of chairs, in which the multiple layers of the seat are glued together using pressure and heat.

STATE OF THE ART

The gluing of the individual layers takes place in large presses, wherein the layers are pressed from their next flat shape at the same time in the desired curved final shape of the seat.

As material for the layers mostly wood furs are used, in which case the seats are referred to as wood press shells or as plywood shell molds. High-pressure laminates (HPL = High Pressure Laminates) are also often used for the outer layers, which may consist of colored papers impregnated with synthetic resin, such as melamine, because they have very good and durable surface properties. The surface does not have to be aftertreated in this case. Melamine is compatible with common wood glue.

As presses for gluing such layers by means of wood glue are in particular high-frequency presses, in which the wood glue is heated due to the water contained in it by the high-frequency radiation and thereby activated. The press and the individual layers - at least when they are essentially dry - are less affected by the high-frequency radiation and remain relatively cold.

For pressing pressures between 100 - 200 N / cm ² , in particular of 200 N / cm ² , applied at temperatures between 60 - 100 ° C.

The seats are superficially smooth and thus quite slippery. It is known to apply an anti-slip on the seat, but this requires a subsequent operation.

PRESENTATION OF THE INVENTION

The invention has as its object to provide a rational method for producing an improved seat shell of the type mentioned, which is not slippery at least in the area of the seat and also looks good and appealing.

The solution of this task according to the invention is that at least one of the two outer layers of the seat shell is provided on the outside before Verleiem with the other layers in the still flat state at least partially with a flocking.

Methods for flocking are state of the art. For flocking, the layer to be flocked is provided with an adhesive application, after which fibers are applied to this adhesive application. Under the action of electrostatic forces, the fibers align themselves perpendicularly to the adhesive application and are fixed in this position during setting or when solidifying the adhesive. The result is a velvety surface.

As has been surprisingly found, the flocking is virtually unaffected by the subsequent pressure and heat treatment in the press to glue the multiple plies and retains virtually 100% of its beneficial properties. This is especially true if the gluing is performed in such a high frequency press that the individual layers including the Belockung and the press remain relatively cold and immediately practically only the glue is heated and this only to an activation temperature of 100 ° C. for In the context of the process according to the invention, the adhesive application must be carried out using a sufficiently heat-resistant adhesive which is not adversely affected by the heat applied during the gluing of the layers. Suitable For this purpose, in particular two-component adhesives, which have a heat resistance greater than 100 °. Of course, the fibers used must also be sufficiently heat-resistant. Fibers made of a polyamide, such as polyamide 6.6, which have this property are particularly suitable for use in the process according to the invention.

The application of the adhesive as well as of the fibers is substantially facilitated by the "flat state" of the layer to be flocked, wherein the term "flat state" should also include a one-dimensionally bent state of the layer, so that the layer is e.g. how a sheet of paper could be redirected around a roll in a printer while being coated with the adhesive and / or fibers.

The application of adhesive can be applied over the entire surface of the surface to be flocked by brushing or spraying. Preferably, however, it is applied only over part of the area, for which the screen printing process is particularly suitable. It can also be decorative surface patterns and with appropriate color choice of the fibers and interesting to be flocked position color contrasts are generated.

As has further been found, as the material for the layer (s) to be blocked, a high-pressure laminate of the type mentioned in e.g. be used with a thickness between 0.3 and 0.9 mm. With only partial flocking this has the advantage that the exposed, non-flocked areas have the good surface properties of this material and require no post-treatment.

The flocking results, as already mentioned, in a decorative, velvety surface, the flocking layer being very thin with a thickness of e.g. only about 1 mm can be performed. However, if desired, the flocking layer may also be substantially thicker, e.g. up to 4 mm thick. The thickness depends on the length of the fibers, the fibers being used in the process according to the invention e.g. may have a length between 0.5 - 4 mm and a thickness of 1 - 20 dtex. Particular preference is given to fibers of about 1 mm in length and about 3.3 dtex in thickness.

The flocks of the type considered are extremely durable, hard-wearing and abrasion-resistant and are not inferior to good upholstery fabrics in terms of resilience and durability. They are air-conditioning, easy to clean, waterproof, skin-friendly, protective and equal tolerances. They contain enough air to prevent sweating, which is of particular importance for seats.

BRIEF EXPLANATION OF THE FIGURES

Fig. 1

den Vorgang der Beflockung;

Fig. 2

in einem Teilschnitt mehrere Lagen einer Sitzschale vor ihrer Verklebung, wobei die oberste Lage beflockt ist;

Fig. 3

die Lagen von Fig. 2 eingelegt In eine noch geöffnete Presse; und

Fig.4

unter a) - d) fertige Sitzschalen mit unterschiedlichen Beflockungsmustern.

The invention will be explained in more detail with reference to embodiments in conjunction with the drawings. Show it:

Fig. 1

the process of flocking;

Fig. 2

in a partial section, several layers of a seat before their bonding, the top layer is flocked;

Fig. 3

the layers of Fig. 2 inserted In an open press; and

Figure 4

under a) - d) finished seats with different flocking patterns.

WAYS FOR CARRYING OUT THE INVENTION

In Fig. 1 1 denotes a layer of a high pressure laminate (HPL) based on a plurality of kraft papers impregnated with melamine resin. The individual layers of the high-pressure laminate are not shown. The thickness of the layer 1 is for example 0.6 mm. The layer 1 could be a so-called endless web, which in Fig. 1 running from left to right through the area shown and, for example, unrolled in front of the area shown on the left of a roll and cut to the right behind the area shown in individual pieces.

With a squeegee 2, the layer 1 is provided over the entire surface by brushing with an adhesive 3 and thus coated under a fiber application device 4 moves through. With the application device 4 short, negatively charged fibers 5 are uniformly applied to the lying at a positive potential layer 1. Due to the electrostatic charge, the fibers 5 are aligned parallel to one another perpendicular to the layer 1. With the setting or hardening of the adhesive of the adhesive application 3, the fibers 5 are fixed. Excess, not fixed fibers 7 are finally removed by suction with a suction device 6. On the layer 1 results in a velvety flock 8.

Fig. 2 shows a layer 1 with a flocking 8 as the top layer of a package from a total of 7 not yet interconnected layers, the flocking 8 is on the outside. The inner layers, designated in total by 9, are, for example, thin wooden furs with a thickness of, for example, 1.2 mm. The bottommost layer 10 could, like the uppermost layer, consist of a high-pressure laminate, but this is provided on the outside instead of with a flocking, for example with a printed or colored decorative layer 11. However, flocking would also be possible here.

From the several layers of Fig. 2 For example, by gluing using pressure and heat in a molding press 12, a seat shell 14 can be made, for example, for a chair. Fig. 3 schematically shows such a press 12 in the still open state, in which a package 13 from several layers according to Fig. 2 is inserted. The glue required for bonding between the layers is not shown. The thin and thus flexible layers adapt when inserted into the press essentially already to their desired final shape. The press 12 is preferably a high-frequency press and the glue is a water-based wood glue.

Fig. 4 shows under a) a finished seat 14 with seat 15 and backrest 16, as shown by the gluing of the package 13 in the molding press 12 of Fig. 3 results. The seat shell 14 is on one side over the entire surface, on the top of the seat 15 and the front of the backrest 16, provided with a flock 8. The flock 8 applied prior to gluing on the uppermost layer 1 was not affected by the pressing process in the press 12.

A full-surface flocking on seat 1 5 and backrest 16 results rationally with the in Fig. 1 illustrated application method for the adhesive application 3 (which could also produce a striped pattern). For seats of chairs, it may be sufficient, however, if only a part of them, such as only the seat 15 is provided with a flocking. Fig. 4 shows under b) a corresponding Embodiment. In c) and d) shows Fig. 4 two further examples in which a partial area flocking pattern is applied on a partial surface such as the seat surface 15, namely in the form of several strips in Fig. 4c) and in the form of a dot pattern in Fig. 4 d) , For these embodiments, for the application of the adhesive application, a different application technique such as the screen printing technique must be used in softer remaining patterns can be produced.

In all embodiments, the flocking may contrast in color to non-flocked surfaces.

NAME LIST

1

Location of a thin high pressure laminate

2

doctor

3

adhesive application

4

Fiber applicator

5

fibers

6

suction device

7

unfixed fibers

8th

flocking

9

inner layers (Holzfuniere)

10

lowest location

11

decorative layer

12

molding press

13

package

14

seat

15

seat

16

backrest

Claims (11)

A method of producing curved, multi-layered seat shells (14), in particular of chairs, in which the multiple layers (1, 9, 10) of the seat pan are glued together using pressure and heat, characterized in that at least one (1) of the two outer layers (1,10) of the seat shell (14) on the outside before gluing with the other layers (9) in the still flat state is at least partially provided with a flocking (8). Method according to claim 1, characterized in that the layer (1) to be flocked is provided with an adhesive coating (3) on its side to be flocked and that thereafter fibers (5) of the flocking (8) are applied by electrostatic forces to this adhesive application (3). be applied. A method according to claim 2, characterized in that as fibers (5) fibers, in particular polyamide fibers, with a length between 0.5 - 4 mm, preferably 1 mm, and with a thickness of 1 - 20 dtex, preferably 3.3 dtex used , Method according to claims 2 or 3, characterized in that the adhesive application (3) is applied over part of the area and preferably in area patterns by screen printing. Method according to one of claims 2 - 4, characterized in that for the adhesive application (3) a heat-resistant adhesive is used, which is not affected by the heat applied during the bonding of the layers and which is in particular a two-component adhesive having a heat resistance greater than 100 ° , Method according to one of claims 1 to 5, characterized in that a high-pressure laminate is used for the layer (s) to be flocked (1). A method according to claim 6, characterized in that the high-pressure laminate is impregnated with melamine resin. Method according to one of claims 1-7, characterized in that for at least one inner layer (9) Holzfumier and for gluing the layers a wood glue is used. Method according to one of claims 1 - 8, characterized in that for the gluing of the layers, a pressure of 1 - 3 N / mm ² , in particular of 2 N / mm ² , is applied. Method according to one of claims 1 - 9, characterized in that for the gluing of the layers, a temperature in the range between 60 - 100 ° C is applied. Method according to one of claims 1 - 10, characterized in that for the gluing of the layers, a high-frequency press is used.

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