EP3285979B1 - Manufacturing method of plates, discs and other shapes using birchbark - Google Patents

Description

Method for producing sheets, disks and other bodies of birch bark pieces, according to the preamble of claim 1. Such a method is known from the document DE102008032940A1 known.

The invention relates to advantageous processing of birch bark pieces into slabs, disks and other bodies with improved surface.

The manufacture of pallets or similar objects made of cellulosic materials and also directly from birch bark is known.

So will in the US 4 221 751 A a method is described in which papermaking foam is reinforced with fibrous material to produce molds.

The WO 95/31710 A1 describes a method for determining the quality parameters of cellulose fibers before, during and also after their processing into final products. Birch wood and birch bark mulch was also investigated.

From the DE 698 23 338 T2 For example, an adhesive composition is known which comprises water-soluble carbohydrates derived from a lignocellulosic material and phenolic compounds provided by an extract of bark, wood or nutshells.

The WO 2012/038594 A1 describes a composite material and a method of making it using wood fiber or wood fiber containing materials and a polymer. The composite material is characterized by improved properties such as increased surface hardness, scratch resistance and other strength properties, low hygroscopicity and biological resistance to fungi and insects.

Furthermore, an antibacterial effect is achieved. Is used here u. a. Birch bark.

• Birkenrinde möglichst großstückig vom Baum abgeschält, nach Größe sortiert und die äußerste Schichtlage entfernt wird,
• größere Birkenrindenstücke nach Größengruppen sortiert und auf ein jeweils einheitliches Flächenmaß geschnitten werden,
• die Birkenrindenstücke mindestens teilweise mit einem Bindemittel benetzt und anschließend geschichtet und unter definiertem Druck zu einem Schichtkörper ausgehärtet,
• und danach aus dem Schichtkörper durch mechanische Bearbeitung Platten, Profile und Körper geformt werden.

From the DE 10 2008 032 940 B4 a method is known in which

• Peeled birch bark from the tree as large as possible, sorted by size and the outermost layer layer is removed,
• larger birch bark pieces are sorted according to size groups and cut to a uniform area size,
• at least partially wetting the birch bark pieces with a binder and then layering and hardening under defined pressure to form a layered body,
• and then from the laminate by mechanical processing plates, profiles and body are formed.

According to a preferred embodiment, after the binder wetting, the birch bark pieces are alternately stacked rotated by 90 ° corresponding to the main fiber direction and glued into a block. By layering with changing fiber direction a higher strength is achieved.

A further advantageous embodiment provides that in the birch bark pieces before the binder wetting in the area a plurality of holes or through holes are introduced by selective impressions, punching or drilling.

In order to achieve a higher strength, even within the birch bark layer, but has the disadvantage that thereby the surface of the plates, profiles and body have irregularities, both haptic and visual nature.

The object of the invention is to improve the surfaces of the plates made of birch bark, profiles and body.

This object is achieved with the features of claim 1. Advantageous embodiments are the subject of the dependent claims. Claims 10 and 11 identify uses.

For a method of making sheets, disks and other bodies of birch bark pieces, the outer layer of which removes, cut to a surface measure, which at least partially wets with a binder, then layered and cured under a defined pressure to form a laminate which mechanically is processed, the invention proposes that the binder is added as filler dust from birch bark.

This has the advantage that voids and unevenness are compensated with a dye of birch bark, which significantly increases the quality of the effective area after the mechanical processing of the laminated body.

On the other hand, the dust as well as the birch bark has antiseptic effect.

Dust with a grain size of less than 0.35 mm is preferably used.

The proportion of the dust should not exceed 40% by weight of the binder.

The binder used is preferably an adhesive.

The birch bark pieces are brushed on both sides in a preferred embodiment prior to wetting with binder, so that the birch bark pieces have perforations.

In this way, a maximum not or poorly glued birch bark component is removed, so that the laminated body receives increased strength.

In a further embodiment of the method, it is provided that the layered body is a block which consists of layers of birch bark pieces stacked on top of one another, wherein at least one layer is composed over its entire area of pieces of birch bark. By combining layers of birch bark pieces, the yield of usable birch bark increases considerably. It is also possible to design the blocks in the length width and height overlooking the desired floor space.

Further, it is advantageous if the main fiber direction of the birch bark pieces of each layer is rectified and superimposed layers have an offset of 90 ° in the main fiber direction.

The thus prepared block of birch bark layers is dissected by cutting at an angle (α) to the surface of the layers along cutting lines in slices or plates or bodies, wherein the cut surfaces form the useful surface. To obtain slices or plates, (α) is preferably 90 ° and the cutting lines are parallel and at equal intervals.

Such plates or slices can then be glued to achieve a larger usable space on a substrate. As support materials wood, wood materials, plastics, metals, screed, etc. are suitable.

Preference is given to plates, tiles or planks, prepared by the described method, used in damp areas and so-called "barefoot zones". These can be shower mats or floors, floors or even wall coverings, room dividers or furniture, etc. Especially in bath, shower and sauna areas, bacterial and fungal transmission is prevented by the antiseptic effect of the birch bark. In addition, there is a very high slip resistance as well as the tactile effect on contact of the usable surfaces by the human skin.

Sliced prismatic bodies may be mechanically processed into cylindrical or spherical or other bodies or combinations thereof and provided with a bore or blind bore so that they can be used as a handle for use by the human hand.

Have proven z. B. door handles or cutlery handles. These look not only good, but are non-slip, ph-neutral and have antibacterial, antifungal and antiviral.

The invention will be explained with reference to the drawing.

The Fig. 1 shows a block 1 of the stacked layers 2.1 - 2.n consists of birch bark pieces 3, wherein the majority of the layers 2 are composed over the entire surface of Birkenrindenstücken 3. This can be seen in the uppermost layer 2.n.

The illustration shows the principle why the layers 2.1 - 2.n were represented by straight lines.
Since the birch bark pieces 3 have different thicknesses and are not even in itself, the natural shape is slightly wavy, with some compensation takes place when curing under pressure.

The main fiber direction of the birch bark pieces 3 of each layer 2 is rectified and superimposed layers 2.1 - 2.2 to 2.n-1 - 2.n have an offset of 90 ° in the main fiber direction.

The cut birch bark pieces 3 have been brushed on both sides before wetting with binder so that the birch bark pieces 3 have perforations.

The binder used has dust from birch bark as a filler, the dust having a particle size of less than 0.35 mm and its weight fraction is preferably between 4 and 40% by weight of the binder.

The birch bark pieces 3 of each layer 2 are adhesively bonded to the respective underlying layer 2. The first layer 2.1 is arranged on a carrier.

The inventive use of the filler in the binder not only in the surface of the layers 2.1 - 2.n existing bumps adjusted color matched, but also possibly existing small butt welds, so that a homogeneous block 1 is present.

Should it be necessary, the block 1 can be trimmed before being further processed into slices 4 or plates or other bodies by at least one cut or brought into a dimensionally stable shape.

The block 1 of birch bark layers 2.1 - 2.n is separated by cuts at an angle α to the surface of the layers 2.1 - 2.n guided along sections 5 in slices 4 with the dimension length L, width B and height H, where α here 90 °, d. H. they are vertical cuts.

The usable area is formed by the cut surface. Such discs 4 or plates can then be glued to achieve greater usable space in shock on a substrate.

It is also possible to disassemble the disks 4 or plates in geometric body and then arrange on a substrate mosaic similar.

By combining sections with α = 90 ° and α ≠ 90 °, prismatic bodies can also be cut out, which can be used as profiles or mechanically processed into cylindrical or spherical or other bodies or combinations thereof.

Provided with a hole or a blind hole cylindrical spherical or other body can be used as handles, in which they are attached, for example, a Erl.

LIST OF REFERENCE NUMBERS

1

block

2

Birch bark layers 2.1 - 2.n

3

Birch bark pieces

4

slices

5

cut lines

L

Length of a disk

B

Width of a disk

H

Height of a disk

α

cutting angle

Claims (9)

1. A method for manufacturing plates, discs, and other bodies using pieces of birch bark, the outer layer of which is removed, which are cut to a surface measure, which are at least partially wetted with a binding agent, then stacked and cured under a defined pressure to form a laminate which is mechanically processed, characterized in that
   birch bark dust is mixed into the binding agent as a filler.
2. The method according to Claim 1, characterized in that the dust has a particle size smaller than 0.35 mm.
3. The method according to Claim 1 or 2, characterized in that
   the weight proportion of the grinding dust is up to 40 wt.% of the binding agent.
4. The method according to any one of Claims 1 to 3, characterized in that
   the pieces of birch bark (3) are brushed on both sides before being wetted with binding agent, so that the pieces of birch bark (3) have perforations.
5. The method according to any one of Claims 1 to 4, characterized in that
   the laminate is a block (1) consisting of layers (2.1 - 2.n) of pieces of birch bark (3) stacked on top of each other, wherein the entire surface of at least one layer (2) is composed of pieces of birch bark (3).
6. The method according to Claim 5, characterized in that the main fibre direction of the pieces of birch bark (3) of each layer (2) is co-directional and layers (2.1 - 2.2 to 2.n-1 - 2.n) have an offset of 90° from the main fibre direction.
7. The method according to Claim 5 or 6, characterized in that
   the block (1) made of birch bark layers (2.1 - 2.n) is segmented into discs (4) or plates or bodies by cuts along cutting lines (5) at an angle (α) to the surface of the layers (2.1 - 2.n), wherein cutting surfaces form the usable surface.
8. The method according to Claim 7, characterized in that
   the plates or discs (4) are glued onto a support material.
9. The method according to Claim 7, characterized in that
   prismatic bodies are mechanically further processed into cylindrical or spherical or other bodies or combinations thereof and are provided with a borehole or blind hole.

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