FI93432B - Method for making a surface layer of parquet - Google Patents

Description

93432

Method for making a surface layer of parquet.

For the purposes of the framework, the park is covered.

The invention relates to a method for producing a surface layer of parquet, in which surface the wood grains are perpendicular or substantially at a non-zero angle to the surface of the parquet surface, and soiuseinämävettä.

There are several advantages to using vertical wood as a surface layer for parquet. Abrasion resistance, hardness and compressive strength are clearly better in the direction of the wood grain than the corresponding values perpendicular to the wood grain.

However, there are several problems associated with the use of vertical wood as a surface layer for parquet, which have not been satisfactorily solved, which is why no commercial breakthrough has been achieved so far. One problem is the drying cracking and post-living (dimensional variation) of vertical wood as a result of moisture fluctuations. Another problem is the porosity of the wood-finished surface. If parquet lacquer layers (e.g. UV-curable urethane 1 lacquers) are applied to the porous surface in the usual manner, the thin lacquer film would break rapidly in wear. There are punctate punctures in the film, through which moisture penetrates the wood and the surface becomes black. Traditional horizontal clay parquets use a wood-non-absorbent primer, which forms a film-like seal between the wood and the topcoat layers. The total consumption of expensive parquet 1 batteries remains relatively small, a total of approx. 30 - 40 g / m2. However, such a parquet-packing technique, in which the base coat is applied directly to the sanded wood surface, would lead to an unfavorable and unsustainable surface structure in the invention.

2,93432

The object of the invention is to provide a method of manufacturing a surface layer of parquet, with which cracking of the surface wood layer as it dries can be avoided and, in addition, stiffness caused by moisture fluctuations can be substantially eliminated.

It is a further object of the invention to further improve this parquet structure and its manufacturing method so that the otherwise good abrasion resistance and hardness of the vertical wood can be further substantially increased, while providing effective additional protection against moisture penetration and effective bonding against residual moisture life forces. may be conventional.

These objects are achieved by the method according to the appended claim 1.

In the following, the method of manufacturing a parquet surface wood layer according to the invention will be illustrated with reference to the accompanying drawings, in which Fig. 1 shows diagrammatically from above the various processing steps of wood slices or boards used in the surface according to the invention.

Figure 2 shows hexagonal wooden slices or tiles treated by the method according to the invention for use in a surface wood layer of parquet.

Figure 3 shows a perspective view of a cross-sectional parquet element made by the method according to the invention.

Fig. 4 shows a cross-section of the parquet layer structure 3 93432 and Fig. 5 shows on a larger scale a vertical section of the parquet surface wood layer, in which the causes of the trees are vertical.

The surface wood layer according to the invention is prepared as follows. Slices or tiles of suitable thickness are cut perpendicularly or at an acute angle against the causes of the wood from a polygonal fresh wood beam. The thickness of the slices or tiles at this stage can be e.g. 14 mm. These wood slices or boards, of which a hexagonal example is shown in Figure 2, are impregnated with a water-soluble polyalcohol, for example polyethylene glycol (PEG). It is intended that the water-soluble impregnant replace a sufficient amount of cell wall water in the wood cells. This prevents the wood from drying out and after-life (dimensional variation) caused by moisture fluctuations. As is known, the moisture life of wood is the result of precisely the amount of water contained in the cell walls, and the swelling and shrinkage of the cell wall caused by its variations.

In order to rapidly and continuously absorb the polyalcohol into the wood, the invention proceeds as follows. Slices or slabs cut from fresh wood are brought to a loading table 6, the conveyor of which transfers the slices or slabs to a microwave oven 7, which heats and partly also evaporates the water inside the wood. The temperature of the wood slices or tiles 1 * coming out of the oven 7 and the water, water vapor and air they contain is in the range of about 40 to 90 ° C. The conveyors 8 and 10 following the furnace 7 are at room temperature, whereby the cooling of the wood and the water vapor and hot air contained therein takes place. As a result, a vacuum is created inside the wood, which helps and accelerates the absorption of polyalcohol inside the wood. Undiluted polyalcohol is drained from the nozzle 9 in the form of a suitably fluidized thin thin film 4 93432 which flows through the gap 8a between successive parts of the track 8 into the receiving chute 9. The film is then applied to Between the tracks 8 and 10, the wood tiles are turned and a polyalcohol film is applied from the nozzle 11 to opposite surfaces of the tiles. Water-soluble polyal alcohol is well absorbed into wood due to its moisture and vacuum. As the polyalcohol, polyethylene glycol having a molecular weight in the range of 600 to 1200 is preferably used. Of course, other water-soluble polyalcohols used in wood treatment which have the ability to replace wood cell wall water can also be considered.

In the next step, the wood slices or boards are led or transported to a heat treatment storage 12 at a temperature of about 50 to 80 ° C. In this heat treatment depot, wood slices or boards are kept for about 1-3 days, during which time the penetration (diffusion) of the polyalcohol progresses deep enough on both sides of the wood board. Thus, the sheets absorbed by the polyalcohol 11a are taken from the heat treatment tank 12 and dried, whereby the water is concentrated as the water is removed. The surfaces of the tiles are sanded and the contours are machined to exact dimensions. The tiles are then glued into 1 parquet blanks, i.e. fastened between two frame layers 4. Fixing to the body layer 4 of the parquet element can be done with resin or wood glue 5 (e.g. polyester resin or polyvinyl acetate glue). As the frame 4, plywood with a thickness of e.g. 9 mm can be preferably used. The body 4 may also comprise one or more layers of reinforced plastic. The blank is sawn through the middle of the wooden boards 1 and the boards are machined into the formed boards, and the sawn surfaces are sanded. After sawing and grinding, the thickness of the vertical surface layer 1 is e.g. 3.0 to 3.5 mm.

A filler resin or varnish is applied to the surface of the wood-finished parquet element, which is allowed to soak inside the causes of the wood and J) 5 93432. The absorption of the filler resin is accelerated in principle in the same way as described above for the absorption of PEG. Thus, the boards are pre-heated, whereby when cooled, they absorb the resin to a sufficient depth inside and between the causes of the wood. Cheap polyester resin is preferably used as the filling resin or varnish, whereby the cost of manufacturing the parquet remains reasonable despite the fact that the amount of resin required due to the porosity of the surface is more than 100 g / m 2, typically 100 to 300 g / m 2, most preferably 150 to 200 g / m 2. In this case, the filling resin or varnish is absorbed in places up to a depth of 0.5 mm and in the majority of the area to a depth of more than 0.2 mm. Thus, the thickness of the filler resin or varnish layer 2 absorbed into the wood varies according to the porosity and absorbency of the wood, but is typically within the above-mentioned limits. It is preferable to use a UV-curable polyester resin in the process, but a conventional thermally activated (accelerated) curing reaction is also possible. The layer formed by the filling resin or varnish 2 substantially increases the wear resistance and hardness of the vertical wood. The surface filling layer also provides additional protection against moisture penetration and at the same time binds the structure against the forces caused by the residual moisture life.

Due to the filling layer 2, the consumption of expensive parquet batteries such as UV-curable polyurethane paints remains at the same level or lower than in conventional board parquets, i.e. it is typically 20 to 50 g / m 2. Thus, there is about 4-5 times more filler resin or varnish to be absorbed into the wood than Parket varnish. For example, the price of a polyester resin is a fraction of the price of a UV-curable urethane varnish used as a parquet 1 window.

The method according to the invention can also be used to produce high-quality parquet from soft wood grades. For example, vertical wood parquet has been made from alder for trial use, with a hardness of about twice and a durability many times higher than normal oak parquet. The wound can also be used to make parquet that is competitive with existing parquet grades in terms of wear resistance and hardness. The same applies to relatives of the wound, e.g. poplar. One insight and advantage of the invention relates precisely to the use of soft wood species. When the compressive strength of soft wood species in the transverse direction is small, the transverse forces that the grain structure can transmit also remain small and the contact life of the parquet remains low for this reason as well.

A single parquet element can be made relatively wide (e.g. 278 mm), so that when using wooden pieces of different shades and sizes / designs, a wide range of collections can be obtained by varying their stacking patterns. The possibility to use cheap wood raw materials such as alder and aspen also makes the parquet structure according to the invention competitively priced.

This method can be used to make ready-made parquet 1. board parquet, but it is also suitable as a real parquet to be fixed directly to the floor, which corresponds to traditional rod parquet, in which the pieces are glued directly to the floor, sanded and varnished.

Il

Claims (8)

A method of producing a parquet surface layer (1), in which the surface layer of the wood fibers runs perpendicularly or at an angle deviating from 0 with respect to the parquet surface pane, and the wooden boards or plates (1) used for the manufacture of the surface layer (1) ') is heated in an oven and spread on the surface of the hot discs or plates in the wood-absorbing water-soluble polyalcohol which replaces the cell wall water of the wood, characterized in that immediately after the spreading of the polyalcohol or in connection therewith the wooden boards are cooled or The plates are so fast that during cooling, the upwardly submerged polyalkylene suction one sucks into the wood and that on the wooden surface finished (4), which is finished on the parquet body (1), the resin or lacquer (2) which is sucked in is spread. in the vertical wood fibers and into them. 2. A process according to claim 1, characterized in that, as polyalcohol, heated polyethylene polyethylene is used without dilution. 3. A method according to claim 1 or 2, characterized in that the slices or plates cut from fresh wood in the transverse direction of the wood fibers are passed through a microwave oven (7) in which the wood and the contents of it are heated to the water, water vapor and air. a temperature range of about 45 - 80 ° C, that the heating time is poured so briefly that substantial drying of the wood does not occur before the water-soluble polyalcohol is spread over the hot wood surface. 4. A process according to any one of claims 1-3, characterized in that the polyalcohol is spread as a film from a nozzle (9, 11) coming over the wooden boards or plates located on a conveyor (8, 10). 93432 5. A process according to any of claims 1-4, characterized in that after the impregnation medium is spread and the cooling stage, the wood boards or plates are poured at a temperature of about 50 - 80 ° C for about 1 to 5 days. Process according to any of claims 1-5, characterized in that the amount of said sealing resin or varnish (2) is above 100 g / m 2, most preferably about 150 - 200 g / m 2, 2 and above. this spreads parquet varnish about 20 - 50 g / m. 7. A process according to claim 6, characterized in that UV-cured polyester resins and as parquet lacquer (1) are used as UV-cured urethane lacquer. Method according to claim 6, characterized in that the filling resin (2) is spread over the surface of the heated parquet element during its cooling stage. il