EP1674224A1 - Process for production of wood fiber insulating panels, and wood fiber insulating panels so produced - Google Patents

Abstract

Manufacturing method involves installing of wood fibers and binding fibers from bale openers over separate weighing devices downstreamed to bale openers in desired mixture ratio equally in blowing line. Wood fibers and binding fibers are conveyed pneumatically to a storage tank through blowing line. Fiber mixture is blown from the storage tank on first transport band under spatial adjustment of fibers. A thermally activated synthetic granule is spread out on the fiber mat over the entire width. The deposited mat defibers at the end of the first transport band and blown after reblending on a second transport band under spatial adjustment of the fiber. The thickness of the deposited mat is adjusted by the velocity of circulation of second transport band, alternatively a fiber mat, fiber core or a foil is applied. The final thickness of the wood fiber insulating board is from 3 to 350 mm, preferably 4 to 250 mm, by calibration and/or compression. Independent claims are also included for the following: (A) Wood fiber insulating board and/or mat; (B) Wood fiber acoustic insulating board; (C) Wood fiber insulating board for absorber or resonator; (D) Wood fiber/Flax fibre-insulating board; (E) Wood fiber impact sound insulating mat for laminating- and parquet-floors; (F) Wood fiber insulating board as surface board in the dry mortarless construction; (G) Wood fiber rafter top insulating board; (H) Wood fiber-WDVS-carrier board; and (I) Passage safe wood fiber insulating board.

Description

The invention relates to a method for producing a wood fiber insulation board or mat and produced by this process wood fiber insulation boards or mats.

The production of wood fiber insulation panels or mats is known. For example, wood fiber insulation boards or mats are produced using the wet process. The plates or mats produced by these methods are relatively thin and the cost of manufacturing high, in particular, incur high costs for drying.

It is also known to produce mats using wood fibers or other fibrous natural products in conjunction with plastic fibers. These mats are made on known from the textile industry carding machines. These plates have only a small thickness. If thicker plates are desired, several of the originally obtained plates are superimposed in layers.

Furthermore, from DE 100 56 829 a process for the production of insulating panels or mats made of wood fibers and plastic fibers is known, in which the plates have a thickness of about 20 mm and are manufactured in one operation. The wood fibers and plastic fibers are mixed together in the desired ratio, loosely sprinkled in a single layer on an endless screen belt, compressed by a arranged above the first wire belt second screen belt or calibrated and then solidified in a downstream heating unit.

The obtained wood fiber insulation panels are characterized by a layered construction, since the fibers are aligned when scattering on the screen belt more or less aligned in one direction, as is generally known from the manufacturing process of MDF boards.

Such plates, which are used for the insulation or for panel production, have a low transverse tensile strength. The individual layers can be easily separated from each other with insulation boards.

In order to increase the transverse tensile strength, it is further known in plate making to spread the starting materials in multiple layers, with the scattering direction rotated by 90 ° in each case. The product obtained is then pressed. This gives the known OSB board (Oriented Strands Board). This product can also be obtained by using the usual procedure. In this case, the mass obtained on the conveyor belt is slightly compressed, the product obtained in the further process process cut into adapted pieces, these in each case by 90 ° offset superimposed and endverpresst. Although the products thus obtained show an improved transverse tensile strength, the production is time-consuming and requires a high investment in equipment.

The invention has for its object to provide a method for the production of wood fiber insulation boards or mats in the dry process, which makes it possible to produce single-layer wood fiber insulation panels or mats with wide thickness range with good transverse tensile strength and compressive rigidity and a large density range.

This object is solved by the characterizing features of claim 1. Particular embodiments can be found in the characterizing features of the subclaims 2 to 14.

According to the invention, the fibers used are aligned in three dimensions. This orientation of the fibers is maintained until final solidification. For carrying out the method, devices are preferably used, as are known for the production of textile fabrics by the nonwoven method. To produce the wood fiber insulation boards or mats according to the invention, the wood fibers are used with a moisture content of 7 to 16%, in particular 12 to 14%.

If wood fibers are used which are obtained in a refiner made of wood pulped, they are previously mixed in a manner known per se with flame retardants and / or water repellents in amounts of 8 to 30%, in particular 10 to 20%, and adjusted to the desired Moisture content dried while removing dust and fibers with small lengths or diameters.

Usually, the addition of the flame retardant and / or water repellents and the drying of the wood fibers takes place separately from the production according to the invention of the wood fiber insulating panels or mats.

The incoming bales of wood fibers and binder fibers are each fed to a bale opener in which the fibers are well opened. In addition to the wood fibers, additional natural fibers, such as hemp, flax, sisal, may be used in addition to the wood fibers in order to achieve certain desired properties in the wood fiber insulation boards according to the invention. Additional bale openers are then provided for these fibers.

According to the desired composition, the individual components are weighed out over separate weighing devices arranged according to the respective bale openers and entered into a blow pipe. Here on the way from the addition of the components to the reservoir intensive mixing by the injected air as a means of transport. The fine synthetic resin fibers adhere well to the excess wood fibers.

For the production of the wood fiber insulation boards or mats according to the invention, the wood fibers are used to bind fibers in mixing ratios of 95 to 80 to 5 to 20% and preferably of 90 to 10%. In these material mixtures up to 30% of the wood fibers can be replaced by other natural fibers.

The intensive mixing of the fibers is continued in the reservoir by the blown in transport air. From the reservoir, the wood fiber binder fiber mixture is weighed evenly over its width after weighing on a surface scale on a first conveyor belt. The amount of supplied fiber mixture depends on the desired layer thickness and the desired density of the produced wood fiber insulation board or mat, the bulk densities are between 20 to 300 kg / m ³ . In the resulting batt, the orientation of the fibers is three-dimensional.

To improve the compressive strength, it is optionally possible to sprinkle onto the pre-fleece a thermally activatable plastic granulate. Plastic granules, such as those used in the recycling of plastic articles from the dual system, are very suitable for this purpose. It is also possible to use granules which consist of a thermally resistant core and a casing of synthetic resins which soften at the temperatures used in the heating zone. The plastic granules can be added in amounts of 5 to 45%, especially in amounts of 10 to 40% and in particular in amounts of 22 to 37%, based on the particular fiber mixture used. A powder spreader ensures a uniform distribution of the scattered plastic granules over the entire width of the fiber web moved on the first conveyor belt. The pre-fleece runs at the end of the first conveyor belt in a Zerfaserungsvorrichtung, wherein again a mixing of the fibers used and the possibly scattered plastic granules. The resulting fiber mixture is inflated to a second conveyor belt and provided for a three-dimensional orientation of the fibers.

By controlling the rotational speed of the second conveyor belt, the layer thickness of the obtained endless mat is adjusted. The layer thickness of the mat can be between 3 to 400 mm. On the endless mats thus obtained may optionally be placed on one or both sides of tissue or nonwovens made of organic, inorganic or natural fibers. Likewise, webs of cellulose or foils are conceivable. The applied fabrics, nonwovens or webs can be structured and / or perforated. Likewise, a coloring is possible. This makes it possible to improve the desired properties of the wood-fiber insulating panels or mats according to the invention.

The wood fiber insulation panels or mats thus obtained are now transferred from the second conveyor belt to an endless oven belt. The oven belt guides the mat through the heating / cooling oven. It is softened by the temperatures prevailing in the furnace, the binder fiber and the resin granules and thus activated. The temperatures in the heating zone are 130 to 200 ° C and in particular 160 to 185 ° C and are obtained for example by blown hot air. Both the binding fibers and the resin granules provide an intimate connection with the wood fibers and possibly laid fabric webs or films.

In the heating oven, a calibration zone connects to the heating zone. The calibration zone is formed by pairs of rollers in which the wood fiber insulation panels or mats in their Thickness evened and, if desired, compressed to the final thickness. Thus, the obtained wood fiber insulation boards or mats are compressed to thicknesses of 3 to 350 mm, in particular 4 to 250 mm.

After calibration, the resulting mats are fed with the oven belt a cooling zone in which the mat is cooled with ambient air.

Coming from the oven belt, the mat is fed to the finished wood fiber insulation panels or mats according to the invention. The mat is trimmed at the edges and then split longitudinally and / or transversely.

The accumulated waste, in particular the edge strips, are comminuted and returned to the process. Since the desired mixing ratio is given, the material can be fed directly into the reservoir.

Thus, by the novel process wood fiber boards or mats produce, which are characterized by the wide range of plate thickness of 3 to 350 mm, in particular 4 to 250 mm at densities of 20 to 300 kg / m ³ and in addition to an improved transverse tensile strength and a show increased pressure stiffness.

The invention further relates to wood fiber insulating panels or mats according to the characterizing features of claims 15 to 25. The invention Holzfaserdämmstoffplatten or mats show a spatial orientation of the wood fibers and the binder fibers and have layer thicknesses of 3 to 350 mm at densities of 20 up to 300 kg / m ³ . The wood fiber insulation panels or mats according to the invention are as acoustic insulation panels, as impact sound insulation mats for laminate or parquet floors, as penetration-resistant insulation board, as thermal insulation composite board, as Innensparrendämmung u.ä. used. By additionally applied on one or both sides webs of nonwovens, fabrics u.ä. from inorganic, organic or natural fibers, or films that may be structured, perforated, dyed, the range of applications of wood fiber insulation panels or mats according to the invention is further increased.

The invention will be explained in more detail by way of examples.

Example 1:

For the production of a wood fiber insulation board 10 parts binding fibers with 90 parts of wood fibers, which were previously provided with flame retardants, mixed and inflated evenly over a reservoir on a first conveyor belt after weighing, so that the density of 30 to 60 kg / m ³ , in particular 35 to 45 kg / m ³ . At the end of the first conveyor belt, the pre-fleece is tufted and inflated after loosening on a second conveyor belt with a thickness between 60 to 250 mm and transferred to the resulting endless mat on the oven belt. After the heating zone, the mat was spent without much compaction, but only homogenization in the cooling zone and then divided to the desired dimensions.

Example 2:

For the production of a wood fiber insulation board as an acoustic panel, as described in Example 1, the Inflated material on the second conveyor belt and covered after building the desired layer thickness on one side with a perforated nonwoven fabric in ribbon form. In the heating furnace, the binding fibers ensure a connection of the wood fibers and a connection of the laid-up fleece to the formed wood fiber insulation board.

Example 3:

For the production of absorbers or resonators 88 parts of wood fibers are mixed with 12 parts of binder fibers and inflated from the reservoir in quantities on a first conveyor belt, which is achieved a bulk density of 35 to 100 kg / m ³ in the mat. After crushing the resulting fleece at the end of the conveyor belt 1, the material is inflated to a second conveyor belt in thicknesses between 30 to 120 mm. The resulting mat is further treated as described in Example 1.

Example 4:

For the production of wood fiber insulating materials for use in acoustics, 10 parts of binder fibers are mixed with 75 parts of wood fibers and 15 parts of flax fibers and uniformly inflated via a storage container onto a first conveyor belt to obtain a final product with a bulk density of 35 to 130 kg / m ³ becomes. Under comminution of the pre-fleece at the end of the first conveyor belt and repeated mixing, the material of the pre-fleece is inflated to a layer thickness of 4 to 200 mm on the second conveyor belt. The resulting continuous mat is further treated as described in Example 1.

Example 5:

For the production of a wood fiber / hemp fiber insulation board 12 parts binder fibers, 60 parts wood fibers and 28 parts hemp fibers are mixed together. The material is inflated uniformly from the reservoir in such quantities on a first conveyor belt, the bulk densities of 25 to 50 kg / m ³ , in particular 25 to 40 kg / m ³ , are obtained. Under repeated mixing of the components of the Vorvlieses from the first conveyor belt, the mass is uniformly inflated to a second conveyor belt. The speed of the second conveyor belt is adjusted so that mat thicknesses of 80 to 250 mm are obtained. The further processing is carried out in the manner described in Example 1.

All of the wood fiber insulation panels or mats obtained in the aforementioned examples exhibit a higher transverse tensile strength than those previously known for the same purposes wood fiber insulation panels or mats.

Example 6:

For the production of wood fiber insulation mats as impact sound mats in laminate or parquet floors 11 parts binding fibers with 89 parts of wood fibers are mixed together and fed to the reservoir. For this, the fiber mixture is inflated to a first conveyor belt to a uniform web, which has a bulk density of 150 to 280 kg / m ³ , in particular 150 to 180 kg / m ³ , has. Before re-mixing the fibers at the end of the first conveyor belt is a plastic granules through a arranged over the entire width of the first conveyor belt powder spreader, as in the recycling of Synthetic resin products obtained from the dual system, added in quantities, which is given in the resulting nonwoven on the second conveyor belt a ratio of wood fibers to binder fibers to resin granules of 55: 7: 38. The mat thickness on the second conveyor belt is 5 to 10 mm. The obtained endless mat of the second conveyor belt is transferred to the oven belt, heated in the heating zone with hot air to 170 to 180 ° C and pulled through the calibration zone. Here a small compression takes place on the final mat thickness of 3 to 8 mm. These mats show in addition to a good transverse tensile strength improved pressure rigidity.

Example 7:

There are 8 parts of binder fiber mixed with 75 parts of wood fibers and 17 parts of hemp fibers and fed to the reservoir. For this, the fiber mixture is uniformly inflated to a first conveyor belt, so that a nonwoven fabric with a density of 130 to 220 kg / m ³ and in particular from 150 to 180 kg / m ³ is formed. After the fibrous web has been formed, granules are added via the powder spreader which consist of a thermally resistant core and a casing of synthetic resins which soften at the temperatures prevailing in the heating zone. The added amount of granules is so high that a part of granules is present on two parts of the fiber mixture. The fiber mixture is well mixed by tearing at the end of the first conveyor belt with the granules and inflated onto the second conveyor belt. In this case, the rotational speed of the second conveyor belt is adjusted so that an endless mat with a thickness of 20 to 22 mm is formed. On the mat on one side of a profiled fabric fleece of cellulose fibers on the entire mat width launched. The product thus obtained is transferred to the oven belt and heated to 170 ° C. At this temperature, the product is driven through the sizing rolls and compacted to the final thickness of 8 to 15 mm. The obtained Holzfaserdämmstoffplatten are excellently suitable as Unterlegplatten in drywall.

Example 8:

For the production of wood fiber insulation boards, which can be used for example as Aufsparrendämmung and walkable but not necessarily puncture-resistant, 11 parts of binder fibers are mixed with 89 parts of wood fibers and fed to the reservoir. From the reservoir, the fiber mixture is inflated in quantities on a first conveyor belt, so that end products have a bulk density of 70 to 150 kg / m ³ and in particular from 100 to 140 kg / m ³ . On the Vorvlies thus obtained are added via a powder spreader granules consisting of a heat-resistant core and a softening in the heating zone sheath and / or consist of resin granules which are obtained in the recycling of plastic articles from the dual system. The amount of added granules is 28 parts granules to 72 parts of the fiber mixture.

The pre-fleece with the scattered granules is crushed and blended well mixed on the second conveyor belt inflated. The speed of the second conveyor belt is set so that the resulting endless mat has a thickness of 65 to 180 mm. In a particular embodiment of this example, the mat can be provided on one side with a dense, moisture-repellent film and on the other side with a fabric fleece.

The prepared from both sides coated mat is passed from the second conveyor belt on the oven belt, heated in the heating zone to 175 ° C and compressed in the calibration to a final thickness of 60 to 160 mm.

In the heating and calibration zone, a good matrix is formed by the softening binder fibers and the granules, into which the wood fibers are embedded and which ensure adequate bonding of the applied film or fabric fleece.

Example 9

For the production of ETICS carrier plates, 12 parts of binder fibers are mixed with 88 parts of wood fibers and fed to a storage container. The procedure is as described in Example 8, with the difference that a bulk density of 80 to 140 kg / m ³ and in particular from 95 to 105 kg / m ^{3 is} achieved and added the granules in amounts of 37 parts to 63 parts of fiber mixture has been. After intimate mixing of the fiber mixture with the granules at the end of the first conveyor belt, the mixture is inflated to a second conveyor belt. The speed of the second conveyor belt is adjusted so that an endless mat with a thickness of 75 to 280 mm is formed. After transfer to the oven belt is heated to 175 ° C and compacted by the sizing to a final thickness of 60 to 200 mm. The resulting plates show excellent compressive stiffness and very good transverse tensile strength.

Example 10:

For the production of puncture proof wood fiber insulation panels, 13 parts of binding fibers with 78 Divide wood fibers and 9 parts of flax fiber mixed and fed to a reservoir. From the storage container, the fiber mixture is inflated onto the first conveyor belt, in quantities that give a plate with a density of 170 to 270 kg / m ³ and in particular from 230 to 250 kg / m ³ . On the formed web on the first conveyor belt granules are spread, which are obtained by recycling of plastic articles from the dual system, in quantities of 36 parts of granules to 64 parts of fiber mixture.

For uniform distribution of the granules in the fiber mixture, the fleece is torn open at the end of the first conveyor belt, the material is well mixed and then inflated to a second conveyor belt. In this case, the rotational speed of the second conveyor belt is adjusted so that an endless mat with a thickness of 25 to 90 mm is obtained.

On this mat a structured fiber fleece, preferably a random fiber fleece over the entire width of the endless mat is placed on one side.

The product thus obtained is transferred to the oven belt and heated in the heating zone to 175 to 185 ° C. In the calibration zone is compressed to a thickness of 15 to 60 mm and then cooled. The spatial arrangement of the fibers is maintained even after calibration. The mats obtained show a high compressive stiffness combined with an increased transverse tensile strength.

Claims (27)

Process for the production of wood fiber insulating boards or mats,
characterized,
that the wood fibers and binder fibers from bale openers via separate, the bale openers downstream weighing equipment in the desired mixing ratio introduced uniformly in a blow pipe and pneumatically fed through the blowpipe to a reservoir, from the reservoir, the fiber mixture is inflated to a first conveyor belt in spatial alignment of the fibers, alternatively on the formed nonwoven fabric, a thermally activated plastic granules is spread evenly over the entire width, the resulting web is fiberized at the end of the first conveyor belt and inflated after further mixing on a second conveyor belt in spatial alignment of the fibers, wherein the thickness of the mat obtained by the Circulating speed of the second conveyor belt is set, alternatively one or both sides of a nonwoven fabric, fiber fabric or a film is placed, the product thus obtained on a furnace transferred belt and is driven on this by the heating / cooling furnace, in which the softening of the binder fiber and the alternatively added plastic granules and thus an intimate bonding of the wood fibers and the one or both sides applied fabric or films, the final thickness of the wood fiber insulation panels or - mats of 3 to 350 mm, preferably 4 to 250 mm, is achieved by calibration and / or compression. A method according to claim 1, characterized in that the ratio of binder fibers to wood fibers 5 to 20 to 95 to 80, preferably from 10 to 90 parts. A method according to claim 1 and 2, characterized in that the wood fibers are replaced by other natural fibers, such as flax, hemp, sisal and fed via separate bale opener with downstream weighing the Blasleitung. Method according to at least one of claims 1 to 3, characterized in that the wood fibers are replaced up to 30% by other natural fibers. Method according to at least one of claims 1 to 4, characterized in that the sprinkled thermally activated resin granules consist of granules obtained during the recycling of plastic parts from the dual system. Method according to at least one of claims 1 to 4, characterized in that the scattered thermally activated plastic granules consist of a thermally resistant core and a sheath of synthetic resins, which soften at the temperatures prevailing in the heating zone. Method according to at least one of claims 1 to 5, characterized in that the thermally activated resin granules in amounts of 5 to 45%, mainly in amounts of 10 to 40% and in particular in amounts of 22 to 37% based on the fiber mixture are sprinkled onto the nonwoven fabric. Method according to at least one of claims 1 to 7, characterized in that the thickness of the endless fiber mat on the second conveyor belt is between 3 to 350 mm. Method according to at least one of claims 1 to 8, characterized in that the fiber webs or fiber webs applied on one or both sides consist of organic, inorganic or natural fibers. Method according to at least one of claims 1 to 8, characterized in that the applied films consist of cellulose or plastic. Method according to at least one of claims 1 to 10, characterized in that the nonwovens, fabrics or films are structured, perforated and / or colored. Method according to at least one of claims 1 to 11, characterized in that in the heating / cooling furnace, the heating zone has a temperature of 130 to 200 ° C and in particular from 160 to 185 ° C. Method according to at least one of claims 1 to 12, characterized in that the heating of the mat in the heating zone immediately the calibration and / or compression to the final thickness and then the cooling takes place. A method according to any one of claims 1 to 13, characterized in that the trimming during trimming and separation of the mat to the desired final dimensions of the wood fiber insulation boards or mats waste is shredded and fed to the reservoir. Wood fiber insulation board or mat, produced by a method according to one of claims 1 to 14, characterized by a thickness of 3 to 350 mm, in particular 4 to 250 mm and bulk densities of 20 to 300 kg / m3. Wood fiber insulation board or mat, produced by a method according to one of claims 1 to 14, characterized by a thickness of 3 to 350 mm, in particular 4 to 250 mm, bulk densities of 20 to 300 kg / m3 and a proportion of resin granules. A wood fiber insulation board produced by a process according to one of claims 1 to 14, characterized by a thickness of 60 to 250 mm and a bulk density of 30 to 60 kg / m ³ , in particular 35 to kg / m ³ . Holzfaserakustikdämmplatte, produced by a method according to any one of claims 1 to 14, characterized by a thickness of 60 to 250 mm and a bulk density of 35 to 45 kg / m ³ and a laid on one side perforated nonwoven fabric. Wood fiber insulation for absorbers or resonators, produced by a method according to one of the claims 1 to 14, characterized by a thickness of 30 to 120 mm and a bulk density of 35 to 100 kg / m ³ . A wood fiber / flax fiber insulation board produced by a method according to any one of claims 1 to 14, characterized by the partial replacement of the wood fibers by flax fibers, a thickness of 80 to 250 mm and a bulk density of 25 to 50 kg / m ³ , in particular 25 up to 40 kg / m ³ . Holzfasertrittschalldämmmatte for laminate or parquet floors, prepared by a method according to any one of claims 1 to 14, characterized by a thickness of 3 to 8 mm, a bulk density of 150 to 280 kg / m ³ , in particular 170 to 255 kg / m ³ and a Proportion of resin granules and a slight compression of the mat obtained on the second conveyor belt in the heating / cooling furnace. Wood fiber insulation board as a shim in dry construction, produced by a method according to one of claims 1 to 14, characterized by a thickness of 8 to 15 mm at a bulk density of 130 to 220 kg / m ³ , in particular from 150 to 180 kg / m ³ , a Proportion of resin granules, a profiled woven fabric applied on one side of the mat obtained on the second conveyor belt and a compaction of the mat in the heating / cooling furnace. Holzfaseraufsparrendämmplatte, produced by a method according to any one of claims 1 to 14, characterized by a thickness of 60 to 160 mm at a bulk density of 70 to 150 kg / m ³ , in particular 100 up to 140 kg / m ³ , a proportion of synthetic resin granules and a compaction of the mat in the heating / cooling furnace. Holzfaseraufsparrendämmplatte, prepared by a method according to any one of claims 1 to 14, characterized by a thickness of 60 to 160 mm at a bulk density of 70 to 150 kg / m ³ , in particular 100 to 140 kg / m ³ , a proportion of resin granules and a On one side of the endless mat formed on the second conveyor belt moisture-repellent film and a laid-up on the other side fabric fleece and a compaction with simultaneous connection of the applied film or the fabric fleece in the heating / cooling furnace. Wood fiber ETICS support plate produced by a process according to one of claims 1 to 14, characterized by a thickness of 60 to 200 mm at a bulk density of 80 to 150 kg / m ³ and in particular from 95 to 105 kg / m ³ , a Proportion of synthetic resin granules and a strong compaction of the endless mat in the heating / cooling furnace. Penetration-proof wood fiber insulation board, produced by a process according to one of claims 1 to 14, characterized by a thickness of 15 to 60 mm at a bulk density of 170 to 270 kg / m ³ , in particular 230 to 250 kg / m ³ , a high proportion of resin granules and a very strong compression of the endless mat in the heating / cooling furnace. Penetration-proof wood fiber insulation board produced by a method according to one of claims 1 to 14, characterized by a thickness of 15 to 60 mm at a bulk density of 170 to 270 kg / m ³ , in particular 230 to 250 kg / m ³ a high proportion of resin granules, applied to one side of the endless mat structured nonwoven fabric and a very strong compression of the Endless mat in the heating / cooling oven.