SI9300440A - a slab for light construction made from wood-wool - Google Patents

Abstract

The invention relates to a light wood-wool building panel with an open-pored structure of compressed wood-wool in which the wood-wool particles are incrusted at the surface with a binder, with the following features: the incrustation has a foam structure which extends at least partially into the pores of the light wood-wool building panel and is introduced during the panel's shaping process by the infiltration of a foamed binder into a wood-wool random structure which is deformed while its volume is reduced at the same time.

Description

Heraklith Baustoffe AG

Lightweight construction panel made of wood wool

The invention relates to a panel for lightweight construction of wood wool with an open-porous framework of compacted wood wool, wherein the wood wool particles are surface-inlaid (released) with a binder.

This type of lightweight wood wool board has long been known under the trade name HERAKLIT (Heraklith).

It is an object of the invention to provide a lightweight wood wool panel of a pre-defined type having a larger pore volume than a conventional Heraklith panel, thus having less dense syllable of wood wool particles and, as a result, needing less binder.

The following technical problems counteract the achievement of this goal: Wood wool particles, which, as is typical, are more than 8 cm in length, 3 to 6 mm wide and 0.2 to 0.5 mm thick, have a completely irregular geometry and are brittle. These particles of wood wool, which may also be present for wood wool snippets, are therefore fundamentally different from fibers which, as is typical, are markedly shorter and thinner and often have a thickness of only a few μτη.

While, for example, fibers may be relatively compressed into a fiber board (rush) or the like, this can only be done with difficulty in the aforementioned pieces of wood wool.

Another problem is the mixing of wood wool particles with a binder. In the prior art, wood wool chips are first peeled off with a binder suspension. The encrusted fragments are then poured into a light bulk and then thickened for the last time, with the condensation maintained for a long time so that the bridges of the binder at the junction points of the adjacent fragments consolidate. With the help of pre-crunching, only relatively strongly compressed panels can be produced in this way, the appearance of which is illustrated in FIG. 1.

The invention is based on the surprising realization that fragile pieces of wood wool can also be made in much smaller thicknesses into a stable panel for lightweight wood wool construction if the binder that connects the particles to each other is prepared as a foam binder. Merely using foam binder instead of the usual binder-shaped binders cannot solve the problem underlying the invention. In the invention, we have learned that individual sections of a strand of wood wool can only be completely surface-encrusted and interconnected if the foam of the binder is inserted into the wood-wool strand during compression. The explanation is this: A strand of wood wool has a density of only 4 to 10 kg / m ³ . In other words, the bulk is up to 90% composed of air. The incrustation of wood wool chips is eliminated with the foam of the binder in a forced mixer. Foam binders would be destroyed (DE 25 48 912 Al) and wood wool chips would be destroyed.

The feed of wood wool particles with a binder foam (as proposed in DE 20 04 246 C3) can be carried out in relatively dense fiber mats, but not in lightly saturated wood wool of extremely low density. Even the power supply of pre-prepared matting, as described in DE 20 04 246 C3, cannot be transferred to lightweight wood wool panels, as covered by the introduction of this description, since pre-pressing power would no longer guarantee complete surface release, which is necessary to create binding points between sections.

According to the relevant consideration, the proposal under DE 1 117 467 BI cannot be transferred to lightweight wood wool boards. There, they first make a mass of binder mortar (binder mortar) and fiber, which is then foamed with a foaming or propellant. For the processing of wood wool chips, the appropriate mass cannot be prepared for the reasons stated above.

This is why the German patent file no. 899 470. This file recommends pouring into molds the way of foam-prepared Sorel cement and waiting for the mass to solidify, with individual particles of wood wool being lodged in the foam.

Obviously, designers can only make discontinuities according to this process. In addition, objects made of foamed Sorel cement are extremely fragile, even if they have filed individual pieces of wood wool or other additives. Technical mass products, such as wood-based wool boards, cannot be manufactured by this process.

Also, by mixing foam binder with filler (wood flour), screeds and other building materials are produced according to DE-AS 1 025 778. By adding artificial resin and / or bitumen to the foam, it is intended to stabilize.

According to the invention, however, the foam stabilizer as well as the mixing process of each type can be dispensed with. In its most general embodiment, the invention relates to a pre-defined panel for lightweight wool construction with an open-porous wood wool frame, wherein the wood wool particles are surface-encrusted with a binder and this encrustation has a foamy structure that extends at least partially into the pores and was introduced during the design process of the board by infiltration of a binder in the form of foam into a strand of wood wool, which at the same time is transformed with the reduction of volume.

The binder, as a foam, is thus (quasi) imprinted in the wood wool filler, in the case of thickening the light wood wool to the desired final dimension. In this way, the binder can first penetrate as a foam into a relatively light fill of wood wool, there the individual pieces are surface-coated and, during further thickening of the wood wool fill, this is optimally distributed. The foam binder is mechanically only minimally loaded so that the foam structure remains almost completely preserved. The thickening of the wood wool backfill is continuous and planar, so that the individual sections can be individually reoriented during the thickening operation, whereby the foam inlay, which has not yet been bonded, acts as an elastic surface layer.

Sketch of FIG. 2 shows a typical structure of a lightweight wool panel according to the invention. Compared to the prior art of FIG. 1 is to detect a structure that is much looser, and thus a pore volume that is much larger (correspondingly noticeably lower density).

Regardless, the strength of this board is surprisingly high. At the same time, the board has excellent sound-technical properties.

The lightweight structure optimizes the use of the board for insulation and damping needs.

The pore space between the frame, formed by thickened wood wool particles, can be more or less completely filled with hardened binder (foam). The fill rate is selected based on the desired product characteristics and usage. It can be influenced, for example, by appropriate additives that match the binder that change the setting time of the foam or pore structure. Such additives (retardants, accelerators, pores) are known in the art and will not be described hereinafter.

This also applies to the binder used only, which can also be constructed of hydraulic cement as well as Sorel cement. Foaming agents such as soaps, surfactants, sulfonates (for example lignosulfonates) as well as metals or metal combinations in the form of powders such as aluminum / zinc or magnesium, as well as hydrogen peroxide, are not described in the art.

They are selected according to one of the embodiments such that the cured binder foam has a density between 100 and 700 g / l and / or pores with a mean diameter between 0.2 and 5 mm.

The typical weight ratio of wood wool: binder foam lies at 1: 6 to 2: 1.

Depending on the area of application of the boards, foam binders may be used, the frame of which will eventually decay. The stability of the lightweight panel of wood wool then depends primarily on the binder contacts between the cuts.

In order to set up a completely purpose-built foam matrix, namely, in the target sections of the board. In this way, it is possible to design the surface of the board with a thin layer of foam without further ado, so that the board has a clean optical through (integral) surface, which can be painted or equipped with a further layer later, for example.

The described panel for light wood wool construction can be made discontinuous and continuous. In each case, a binder in the form of a foam is applied to at least one flat section of the loose wood wool filler, which is then infiltrated with the simultaneous reduction of the wood wool fill volume. In this way, the plate, thus pressed and infiltrated in the form of a foam, is kept stable in volume, until the binder (foam) is reached in strength.

A continuous process is particularly easy to achieve if the binder is applied as foam to a continuous strand of wood wool strands and then infiltrated into the wood wool squeeze (to the desired final dimension of the board).

A further optimization of the process is that the binder is introduced as a foam between two continuously occurring strands of wood wool and ribbons and, while simultaneously infiltrating the binder into the wood wool strands, is guided to one another and concentrated into a single plate.

In this case, the foam, therefore, quasi-isotropically invades the wood wool backbone on both sides, which are simultaneously interconnected into a single plate.

The following description of the sketch details this manufacturing process in detail.

Here is a sketch of FIG. 3 for pure transparency designed purely schematically.

On the first conveyor belt 10 moving in the direction of arrow T, a loose strand 12A of wood wool is formed.

By moving above lane 10, a second conveyor belt 14 is received, which receives a foam binder 12C, which at its end transfers it to a loose strand 12A of wood wool.

Again, at the offset, a third conveyor belt 16 is disposed above lane 14 through which a second partial flow 12B of wood wool strands flows, flowing onto the strand 12A and the binder 12C (foam) thereon, resulting in the first infiltration of the binder in strands 12A 12B wood wool.

In the following, initially the loose material 12A, 12B of wood wool and the binder 17 inserted between them are continually thickened through the cylinders 18, while during this thickening the foam of the binder 12C penetrates into the cavities of the 12A, 12B wood wool and individual pieces of surface it releases (encrustes) as well as fills the corresponding pore void between the cuts.

This is followed by a thickening to the desired final dimension 20, until the foam binder is sufficiently bonded so that the fabricated plate exhibits sufficient inherent stability so that it can be removed and further processed. Further machining steps are, in particular, trimming to the desired final dimension, as well as, if necessary, surface finishes and / or the manufacture of plywood parts by gluing other panels or the like.

Claims (10)

Patent claims 1. Lightweight wool panel with open-porous thickened wool frame, wherein the wood wool particles are surface-inlaid with a binder, characterized in that the encrustation has a foam structure that extends at least partially into the pores of the slabs. lightweight wool construction and which was introduced during the process of designing lightweight wool board by infiltration of the binder as a foam into the wood wool fill, which is transformed at the same time as the volume is reduced. Panel according to claim 1, characterized in that the pore space between the framework of thickened wood wool particles is completely filled with a hardened binder like foam. Panel according to claim 1 or 2 _x, characterized in that the hardened foam binder has a density between 100 and 700 g / l. Panel according to one of Claims 1 to 3, characterized in that it has a cured foam binder with a pore diameter of between 0.2 and 5 mm in diameter. Panel according to one of Claims 1 to 4, characterized in that the weight ratio of wood wool: foam binder is 1: 6 to 2: 1. Plate according to one of Claims 1 to 5, characterized in that the release of the hardened binder is provided in the form of a foam covering the surface (s) of the plate. 7. A process for making a lightweight wool panel according to any one of claims 1 to 6, characterized in that a binder in the form of a foam is applied to at least one planar section of loose wood wool, and subsequently to a desired reduction of the wood wool volume. the final dimension of the lightweight wood wool board is infiltrated into the foam binder, so that the compacted and infiltrated foam binder is kept in volume stability by volume until it reaches its strength (after bonding the foam binder) ). A method according to claim 7, characterized in that the foam binder is applied continuously to the strip of incoming wood wool strands and then infiltrated when the wood wool sanding is compacted to the desired final dimension for lightweight construction. Method according to claim 7 or 8, characterized in that the binder in the form of foam is inserted between two continuously incoming strands of wood wool and strips and then, while simultaneously infiltrating the binder in the form of foam, into the wood wool strands, and concentrate on each other. the desired final dimension of the panel. Method according to one of Claims 7 to 9, characterized in that a binder is provided in the form of a foam containing the curing time of the modifying and / or pore structure of the influent.