CA2306630A1 - Wood component and a method for the production and application of the same - Google Patents
Wood component and a method for the production and application of the same Download PDFInfo
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- CA2306630A1 CA2306630A1 CA002306630A CA2306630A CA2306630A1 CA 2306630 A1 CA2306630 A1 CA 2306630A1 CA 002306630 A CA002306630 A CA 002306630A CA 2306630 A CA2306630 A CA 2306630A CA 2306630 A1 CA2306630 A1 CA 2306630A1
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- wood
- component
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27M—WORKING OF WOOD NOT PROVIDED FOR IN SUBCLASSES B27B - B27L; MANUFACTURE OF SPECIFIC WOODEN ARTICLES
- B27M1/00—Working of wood not provided for in subclasses B27B - B27L, e.g. by stretching
- B27M1/06—Working of wood not provided for in subclasses B27B - B27L, e.g. by stretching by burning or charring, e.g. cutting with hot wire
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/0006—Working by laser beam, e.g. welding, cutting or boring taking account of the properties of the material involved
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
- B27K5/003—Treating of wood not provided for in groups B27K1/00, B27K3/00 by using electromagnetic radiation or mechanical waves
- B27K5/005—Laser-light
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
- B27K5/00—Treating of wood not provided for in groups B27K1/00, B27K3/00
- B27K5/06—Softening or hardening of wood
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2103/00—Materials to be soldered, welded or cut
- B23K2103/30—Organic material
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Optics & Photonics (AREA)
- Plasma & Fusion (AREA)
- Electromagnetism (AREA)
- Chemical And Physical Treatments For Wood And The Like (AREA)
Abstract
The invention relates to a wood component in which the wood has altered properties in geometrically defined areas. Said geometrically defined areas exclusively comprise the properties of solidified melting wood. The invention also relates to a method for producing such components and to the application of said component.
Description
A6-A4-,00 13:48 TUD DEZ.S SG 5.1 ID= +49 351 4637170 S.02 Wood component and ~a method for the production and application of the same Description The invention relates to a w ~ od component in which the wood has altered properties in geo-metrically defined areas. Th~ invention also relates to a method for producing such compo-nents and to the application ~f said component. 1'he ixivention can be employed in the wood-working and wood processi ~ industries, in the building arid construction industries, and in the craft and trade.
In woodworking, lasers are sed for, in addition to surveying processes, cutting and piercing processes. A novel applicati n field is the removal of material using laser irradiation. Selt man, J.: Freilegen der Holzs durch UV-Bestrahlung (Laying bare of the wood structure by UV-irradiation), I-Iolz al~ Roh- and Werkstoff, Springer-Verlag, 53(1995), pp. 225-228;
and Panzncr, M. et al.: Experimental Investigation of the Laser Ablation Process on Wood Surfaces, Fourth Inteniatio Conference on Lascr Ablation COLA, Monterey, California, 1997 describe different s' ibilities arid methods for the removal of the wood layer spoiled by mechanical removing prq~cesses using electromagnetic beams of different wavelengths.
From DE 94 02 G8I.5 U1, ~ device is known for the processing of glass, plastics, semicon-ductors, wood or ceramics, hick uses laser radiation from a laser radiation source that emits laser radiation in form of a l~ser beam, focussing this laser radiation through a focussing opti-w w This device is designed to a able an effective removing mechanism which is designed to heat the ,material to be processed ery heavily in the range of wavelengths of 1.4 Ltm to 3.0 pm so that so-called micro-explosi ns occur. The heated material is removed. This process is used cal system onto a glass, pl ' tic, semiconductor, wood or ceramic material component. 'Ibis device is characterized in tlialt the laser radiation used has a wavelen h of l .4 m to 3.0 m.
for marking components o~ generating mechanical stresses in glass tubes to subsequently break them in a melting zonel,.
In DE 40 33 2SS A1 a mcth~d is described that is designed to upgrade wood veneers for vis-ual effect by emphasizing t a grain. This is reached by pyrolytic browning of the wood sur-face using IR-radiation. The alterations following the laser cutting of wood and wood materi-als were investigated, amo others, by Parameswaraa, N.: Feinstrukturelle Veriinderungen an durch Laserstratil getr~nnten Schnittfl~.chen von Holz and Holzwerkstoffen (Fine-A6-A4-90 13:48 TUD DEZ.S SC 5.1 ID= +49 351 4637170 S~A3 structural alterations of laser-cut surfaces of wood and wood materials), Holz als Roh- and Werkstoff, Berlin 40(1982) 1, pp. 421-X28, who found the following: The brown to black colour of the cutting surfac Ids is due to the mainly thermal cutting process and typical of a pyrolysis in the cellular ar I of separating. A surface largely melted down is produced which very much reduces the diam tens of the cell lamina. The high temperatures in the cutting kerf (approx. 700 °C, Arai et al. 1979) lead to a gradual.transformation of the wall components into a glassy body. Back, E.Z.,.: Cellulose bci hohen Temperaturen:
Selbs~tvernetzung ... (Cel-lulose at high temperatures: self cross-linking ...), Das Papier, 27(1973), pp. 475-483, theo-retically detcnnined the mel~ng temperature of cellulose of approx. 450 °C based on the glass temperature. Further, he foul~d that melting without pyrolytic side effects will only be possi-ble if heating and cooling occur in a sufiflciently short period of time.
The above-mentioned melting processes when processing wood are considered to be adverse side effects. To date, no alterations of specific wood properties has been created.
In addition to the typical p~rolytical degradation processes when wood is laser-processed, melting is also known as a s ndary transformation process. As a rule, melted areas are con-sidered negative concerning a quality of the wood surface processed.
Additionally, the py-rolytical degradation produ~ generated in processing are held and solidified in the melt.
Known methods, such as las~~ r dividing, confine theirselves to evaporating wood substance by thermal or photochemical ~pling of the laser during processing. Thereby, the alteration of the wood structure in the are ~ adjacent to the processing zone is arbitrary.
Degradation .proc-esses are not controllable, c hardly be avoided, and lead to a reduced quality of the wood processed in this way. Diffe nt methods, such as plasma processing (DE 41 35 697 A1), re-quire much effort to prepare the wood and complicated jigs, which prevents the industrial-scale applicarion.
It is the objective tion of this inv to describe a wood component as well as a method for the production and applicationsaid o component, in which, in geometrically defined areas, the wood has altered loch properties that chemically and physically, systematically altered prop-erties of the wood low. This is to avoid any treatment of surface fo the wood surface other-wise necessary, and numlxr to open of new possible uses and fields of application of wood.
According to the invention, a problem is solved using a wood component having the prop-erties listed in Claim 1. A eat number of component versions follow from the dependent claims. Further, the problem is solved using a process having the properties listed in Claim 11. Versions of the process fqllow from the dependent claims. Applications of the component follow from the Claims 22 to I28.
06-04-9A 13:49 TUD DEZ~5 SG 5.1 ID= +49 351 4637170 S.A4 The wood component has alt~red properties in geometrically defined areas.
According to the invention, the geometrically efined areas have exclusively the properties of solidified wood melts. In the context of the ependent Claims 2 to 10 it follows that said areas are single or several wood cells or single or several cell walls. From the melting together, alterations of properties of physical and chemical nature as well as tailored alterations of the deformation behaviour follow.
According to the Claims 22 ~0 28, the melt can be used for the production of joints of wood com vents and/or wood p ~ 'cles, or, respectively, reinforcements can be incorporated into po the melt.
The main constituents of wo ~ d, cellulose, lignin and hemicelluloses, similar to other polymers have no melting point but th;era is a wide transition interval in phase transformation. In con-trast to plastics, wood has ~ o homogeneous structure and, hence, no softening point but a softening temperature range In wood, thermal degradation processes already start at tem-peratures lower than 100 °C~. However, the critical factor for the beginning and progress of pyrolysis is the dtuation of heat influence, since pyrolysis is a continuous course of successive degradation processes. Soft~ning starts at temperatures about 100 °C, progressing with a quickly decreasing degree o~ polymerization of the chains and beginning plasticization. Mol-ten wood is characterized in that it has a low degree of polymerization, increased proportion of amorphous substance, los fibrillar structure of the cellulose and typical cell structure, ho-mogenization axed increased ~ elting temperature when repeatedly heated.
a oduction of wood com vents is established Accordingly, the method to ,CIaIm I 1 for th pr po such that the geometrically defined areas are melted by contact-free, short-time, preferably within less than or equal 50 s, high energy input, so that the degree of polymerization of the chains decreases quickly an~plasticization begins, and the melt solidifies within this period of time.
Advantageously, laser light is used as the electromagnetic radiation. The scope of the interac-tion zone, the interaction pe I'od and the intensity are realized by a combination of the relative movement between beam d workpiece as well as through methods of dynamic beam form-ing. Processing is in a gas atmosphere defined by composition, pressure and temperature.
1-leating can be in an inert las atmosphere as well as in free atmosphere. The process of the invention can be combinedith other methods of woodworking, e.g. mechanical processing.
Melting can be used within ~ defined time regime shortly before, during, or shortly after proc-essing using another 06-04-00 13:49 TUD DEZ.S SG 5.1 ID= +49 351 4637170 S.05 ' 4 From the invention, the foil wing advantages result. Melting makes possible to change the structure of wood. Closing tl~e wood cells directly leads to a decrease of the specific surface and the capillary take-up of Z~umidity is reduced, or prevented, respectively.
Wood and wood particles can be joined with ei ch other by welding without any, or using solely wood-inherent (e.g. lignin) fihing materials. By melting, wood can be joined with other materials, especially transparent polymers or fibr us materials. Melting is possible in a locally limited space or on a complete surface, whereb the proportion of melted volume has a geometrically defined magnitude on or below the ~urface, thus also defining the degree of alteration of physical and/or chemical properties. .$y melting, tailored physical and/or chemical alterations arc pro duced in the wood. To reap I a this, also extraneous substances can be melted into the wood.
Said extraneous substances an be particles and/or pigments. Before the melting process they are applied into or onto the ood through, for example, impregnating, immersing, coating, or during the melting process,~or example, by means of a gas or powder beam. The diffusion properties of the wood to ambient media are changed. The diffusion properties in the main cutting directions of the wood are essentially homogeneous in melted areas.
Melting leads to I
hydrophobing of the wood urface. Due to the tailored physical and/or chemical alterations, melted wood has an improv d resistance to wood pest. Hardness and abrasion resistance of the wood surface can be ad usted. The optical properties (absorptivity, reflectivity and dif fusing power) of the wood surface are deliberately altered. The lustre of melted wood is clearly different from that of unmelted wood. Softening of wood substance in the range of glass temperature offers nov~l possibilities for the deformation of wood.
In the following, the inventiøn is further explained by examples of embodiment.
In order to protect the end o~ an 8 cm x 10 cm cross-sectioned wood beam from capillary wa-ter absorption, a closed su~ace of melted wood with a maximum thickness of 0.5 mm was produced in the range of thGl cross-cut grain. To produce this melted area the laser beam of a continuous C02-laser with power of 2500 W and a laser spot diameter of 6 mm was mean-dered over the cross-cut s ace to be processed of the beam end using a double-mirror scan-ner, with a track overlap of 0 percent and a velocity of 6 m/s.
In order to produce a hom 'geneous, closed melted zone with a thickness of more than 0.4 mm, the cell structure withi the geometrically defined area must be abolished.
Therefore, the wavelength and duration of a laser action were chosen such that the solid wood constituents were melted to a depth of a rox. 0.8 mm.
06-04-.0A 13:50 TUD DEZ.5 SG 5.1 ID= +49 351 4637170 5.06 The decreased capillary wa' absorption was evaluated by wetting with a defined water vol-ume and measurement of th~time until the complete penetration of the water.
The investi ga_ tion of the melted wood s ce showed a penetration time prolonged by the factor 7.1.
Two spruce veneers 3 were elded together by melting of the lignin contained in the wood.
To this end, the veneers 3, Irst, were smoothed by ironing and fixed in a suitable ftxture so that they lie close together ithout any clearance over the whole weld length.
To produce a weld S the laser beam 2 of a continuous COz-laser with a power of 2SU0 W, a spot diameter of 13 mm and a velocity of 12 m/s was linearly moved over the prepared weld area.
In order to produce a homogeneous closed weld S of a thiclmess of, at least, O.S mm, the cell i structure within the geometrically defined area must be abolished. Therefore, the wawclcngth and duration of the laser b iam 2 were chosen such that the solid wood constituents were melted to a depth of approx. ~ mm.
After processing, both venee#s 3 arc joined with each other by the weld 5.
After separating the two veneers from each othe I;, the microscope clearly shows a fracture edge over the whole weld length. Below the fract~e edge a homogeneous melt layer is observed. The cell struc-ture is abolished down to a deb ptb of 0.4 mtn.
,, . . . . .
A6-A4-9A 13:50 TUD DEZ.S SG 5.1 ID= +49 351 4637170 S.07 Nomenclature 1 Beam guiding 2 Laser beard 3 V eueer 4 Processing direction Weld 6 Melt
In woodworking, lasers are sed for, in addition to surveying processes, cutting and piercing processes. A novel applicati n field is the removal of material using laser irradiation. Selt man, J.: Freilegen der Holzs durch UV-Bestrahlung (Laying bare of the wood structure by UV-irradiation), I-Iolz al~ Roh- and Werkstoff, Springer-Verlag, 53(1995), pp. 225-228;
and Panzncr, M. et al.: Experimental Investigation of the Laser Ablation Process on Wood Surfaces, Fourth Inteniatio Conference on Lascr Ablation COLA, Monterey, California, 1997 describe different s' ibilities arid methods for the removal of the wood layer spoiled by mechanical removing prq~cesses using electromagnetic beams of different wavelengths.
From DE 94 02 G8I.5 U1, ~ device is known for the processing of glass, plastics, semicon-ductors, wood or ceramics, hick uses laser radiation from a laser radiation source that emits laser radiation in form of a l~ser beam, focussing this laser radiation through a focussing opti-w w This device is designed to a able an effective removing mechanism which is designed to heat the ,material to be processed ery heavily in the range of wavelengths of 1.4 Ltm to 3.0 pm so that so-called micro-explosi ns occur. The heated material is removed. This process is used cal system onto a glass, pl ' tic, semiconductor, wood or ceramic material component. 'Ibis device is characterized in tlialt the laser radiation used has a wavelen h of l .4 m to 3.0 m.
for marking components o~ generating mechanical stresses in glass tubes to subsequently break them in a melting zonel,.
In DE 40 33 2SS A1 a mcth~d is described that is designed to upgrade wood veneers for vis-ual effect by emphasizing t a grain. This is reached by pyrolytic browning of the wood sur-face using IR-radiation. The alterations following the laser cutting of wood and wood materi-als were investigated, amo others, by Parameswaraa, N.: Feinstrukturelle Veriinderungen an durch Laserstratil getr~nnten Schnittfl~.chen von Holz and Holzwerkstoffen (Fine-A6-A4-90 13:48 TUD DEZ.S SC 5.1 ID= +49 351 4637170 S~A3 structural alterations of laser-cut surfaces of wood and wood materials), Holz als Roh- and Werkstoff, Berlin 40(1982) 1, pp. 421-X28, who found the following: The brown to black colour of the cutting surfac Ids is due to the mainly thermal cutting process and typical of a pyrolysis in the cellular ar I of separating. A surface largely melted down is produced which very much reduces the diam tens of the cell lamina. The high temperatures in the cutting kerf (approx. 700 °C, Arai et al. 1979) lead to a gradual.transformation of the wall components into a glassy body. Back, E.Z.,.: Cellulose bci hohen Temperaturen:
Selbs~tvernetzung ... (Cel-lulose at high temperatures: self cross-linking ...), Das Papier, 27(1973), pp. 475-483, theo-retically detcnnined the mel~ng temperature of cellulose of approx. 450 °C based on the glass temperature. Further, he foul~d that melting without pyrolytic side effects will only be possi-ble if heating and cooling occur in a sufiflciently short period of time.
The above-mentioned melting processes when processing wood are considered to be adverse side effects. To date, no alterations of specific wood properties has been created.
In addition to the typical p~rolytical degradation processes when wood is laser-processed, melting is also known as a s ndary transformation process. As a rule, melted areas are con-sidered negative concerning a quality of the wood surface processed.
Additionally, the py-rolytical degradation produ~ generated in processing are held and solidified in the melt.
Known methods, such as las~~ r dividing, confine theirselves to evaporating wood substance by thermal or photochemical ~pling of the laser during processing. Thereby, the alteration of the wood structure in the are ~ adjacent to the processing zone is arbitrary.
Degradation .proc-esses are not controllable, c hardly be avoided, and lead to a reduced quality of the wood processed in this way. Diffe nt methods, such as plasma processing (DE 41 35 697 A1), re-quire much effort to prepare the wood and complicated jigs, which prevents the industrial-scale applicarion.
It is the objective tion of this inv to describe a wood component as well as a method for the production and applicationsaid o component, in which, in geometrically defined areas, the wood has altered loch properties that chemically and physically, systematically altered prop-erties of the wood low. This is to avoid any treatment of surface fo the wood surface other-wise necessary, and numlxr to open of new possible uses and fields of application of wood.
According to the invention, a problem is solved using a wood component having the prop-erties listed in Claim 1. A eat number of component versions follow from the dependent claims. Further, the problem is solved using a process having the properties listed in Claim 11. Versions of the process fqllow from the dependent claims. Applications of the component follow from the Claims 22 to I28.
06-04-9A 13:49 TUD DEZ~5 SG 5.1 ID= +49 351 4637170 S.A4 The wood component has alt~red properties in geometrically defined areas.
According to the invention, the geometrically efined areas have exclusively the properties of solidified wood melts. In the context of the ependent Claims 2 to 10 it follows that said areas are single or several wood cells or single or several cell walls. From the melting together, alterations of properties of physical and chemical nature as well as tailored alterations of the deformation behaviour follow.
According to the Claims 22 ~0 28, the melt can be used for the production of joints of wood com vents and/or wood p ~ 'cles, or, respectively, reinforcements can be incorporated into po the melt.
The main constituents of wo ~ d, cellulose, lignin and hemicelluloses, similar to other polymers have no melting point but th;era is a wide transition interval in phase transformation. In con-trast to plastics, wood has ~ o homogeneous structure and, hence, no softening point but a softening temperature range In wood, thermal degradation processes already start at tem-peratures lower than 100 °C~. However, the critical factor for the beginning and progress of pyrolysis is the dtuation of heat influence, since pyrolysis is a continuous course of successive degradation processes. Soft~ning starts at temperatures about 100 °C, progressing with a quickly decreasing degree o~ polymerization of the chains and beginning plasticization. Mol-ten wood is characterized in that it has a low degree of polymerization, increased proportion of amorphous substance, los fibrillar structure of the cellulose and typical cell structure, ho-mogenization axed increased ~ elting temperature when repeatedly heated.
a oduction of wood com vents is established Accordingly, the method to ,CIaIm I 1 for th pr po such that the geometrically defined areas are melted by contact-free, short-time, preferably within less than or equal 50 s, high energy input, so that the degree of polymerization of the chains decreases quickly an~plasticization begins, and the melt solidifies within this period of time.
Advantageously, laser light is used as the electromagnetic radiation. The scope of the interac-tion zone, the interaction pe I'od and the intensity are realized by a combination of the relative movement between beam d workpiece as well as through methods of dynamic beam form-ing. Processing is in a gas atmosphere defined by composition, pressure and temperature.
1-leating can be in an inert las atmosphere as well as in free atmosphere. The process of the invention can be combinedith other methods of woodworking, e.g. mechanical processing.
Melting can be used within ~ defined time regime shortly before, during, or shortly after proc-essing using another 06-04-00 13:49 TUD DEZ.S SG 5.1 ID= +49 351 4637170 S.05 ' 4 From the invention, the foil wing advantages result. Melting makes possible to change the structure of wood. Closing tl~e wood cells directly leads to a decrease of the specific surface and the capillary take-up of Z~umidity is reduced, or prevented, respectively.
Wood and wood particles can be joined with ei ch other by welding without any, or using solely wood-inherent (e.g. lignin) fihing materials. By melting, wood can be joined with other materials, especially transparent polymers or fibr us materials. Melting is possible in a locally limited space or on a complete surface, whereb the proportion of melted volume has a geometrically defined magnitude on or below the ~urface, thus also defining the degree of alteration of physical and/or chemical properties. .$y melting, tailored physical and/or chemical alterations arc pro duced in the wood. To reap I a this, also extraneous substances can be melted into the wood.
Said extraneous substances an be particles and/or pigments. Before the melting process they are applied into or onto the ood through, for example, impregnating, immersing, coating, or during the melting process,~or example, by means of a gas or powder beam. The diffusion properties of the wood to ambient media are changed. The diffusion properties in the main cutting directions of the wood are essentially homogeneous in melted areas.
Melting leads to I
hydrophobing of the wood urface. Due to the tailored physical and/or chemical alterations, melted wood has an improv d resistance to wood pest. Hardness and abrasion resistance of the wood surface can be ad usted. The optical properties (absorptivity, reflectivity and dif fusing power) of the wood surface are deliberately altered. The lustre of melted wood is clearly different from that of unmelted wood. Softening of wood substance in the range of glass temperature offers nov~l possibilities for the deformation of wood.
In the following, the inventiøn is further explained by examples of embodiment.
In order to protect the end o~ an 8 cm x 10 cm cross-sectioned wood beam from capillary wa-ter absorption, a closed su~ace of melted wood with a maximum thickness of 0.5 mm was produced in the range of thGl cross-cut grain. To produce this melted area the laser beam of a continuous C02-laser with power of 2500 W and a laser spot diameter of 6 mm was mean-dered over the cross-cut s ace to be processed of the beam end using a double-mirror scan-ner, with a track overlap of 0 percent and a velocity of 6 m/s.
In order to produce a hom 'geneous, closed melted zone with a thickness of more than 0.4 mm, the cell structure withi the geometrically defined area must be abolished.
Therefore, the wavelength and duration of a laser action were chosen such that the solid wood constituents were melted to a depth of a rox. 0.8 mm.
06-04-.0A 13:50 TUD DEZ.5 SG 5.1 ID= +49 351 4637170 5.06 The decreased capillary wa' absorption was evaluated by wetting with a defined water vol-ume and measurement of th~time until the complete penetration of the water.
The investi ga_ tion of the melted wood s ce showed a penetration time prolonged by the factor 7.1.
Two spruce veneers 3 were elded together by melting of the lignin contained in the wood.
To this end, the veneers 3, Irst, were smoothed by ironing and fixed in a suitable ftxture so that they lie close together ithout any clearance over the whole weld length.
To produce a weld S the laser beam 2 of a continuous COz-laser with a power of 2SU0 W, a spot diameter of 13 mm and a velocity of 12 m/s was linearly moved over the prepared weld area.
In order to produce a homogeneous closed weld S of a thiclmess of, at least, O.S mm, the cell i structure within the geometrically defined area must be abolished. Therefore, the wawclcngth and duration of the laser b iam 2 were chosen such that the solid wood constituents were melted to a depth of approx. ~ mm.
After processing, both venee#s 3 arc joined with each other by the weld 5.
After separating the two veneers from each othe I;, the microscope clearly shows a fracture edge over the whole weld length. Below the fract~e edge a homogeneous melt layer is observed. The cell struc-ture is abolished down to a deb ptb of 0.4 mtn.
,, . . . . .
A6-A4-9A 13:50 TUD DEZ.S SG 5.1 ID= +49 351 4637170 S.07 Nomenclature 1 Beam guiding 2 Laser beard 3 V eueer 4 Processing direction Weld 6 Melt
Claims (23)
1. Wood component in which the wood has altered properties in geometrically defined near-surface areas characterized in that said geometrically defined near-surface areas have the properties of solidified wood melts free from pyrolytic degradation products.
2. Component to Claim 1 characterized in that the geometrically defined near-surface areas are cell walls melted in one or several cutting directions so that the diffusion resistance in said geometrically defined areas to ambient media rises independent of the cutting direction.
3. Component to Claim 1 or 2 characterized in that said geometrically defined near-surface areas are visually different from non-melted wood in their optical properties absorptivity, reflectivity and diffusing power, and hence, lustre.
4. Component to any of the above-mentioned Claims characterized in that the geometrically defined near-surface areas have a higher hardness and abrasion resistance.
5. Component to any of the above-mentioned Claims characterized in that the deformation behaviour in the geometrically defined near-surface areas is altered compared with the original state.
6. Component to any off the above-mentioned Claims characterized in that the bulk of the solidified wood melt is in a geometrically defined area of the component below the surface.
7. Component to any of the above-mentioned Claims characterized in that the physical and/or chemical properties of the areas are altered by substances incorporated into the solidified wood melt,
8. Component to Claim 1 characterized in that the incorporated substances are particles and/or pigments.
9. Method for producing a wood component to any of the about-mentioned claims characterized in that a locally limited or full-area contact-free short-time high energy input into the wood component occurs by electromagnetic waves, whereby a proportion of melted volume of geometrically defined magnitude at or below the surface of the component is produced with the energy input dimensioned such that the proportion of melted volume is produced without pyrolytic degradation processes.
10. Method to Claim 9 characterized in that electromagnetic waves in form of laser light are used.
11. Method to Claim 9 or 10 characterized in that the duration of the energy input is up to 50 ms.
12. Method to any of the Claims 9 to 11 characterized in that the energy input is carried out through electromagnetic radiation that can be controlled extremely accurately and quickly regarding the lateral extension of the range of interaction, time of interaction and intensity, having a wavelength adapted to the desired depth of the range of interaction.
13. Method to any of the Claims 9 to 12 characterized in that the process is carried out under inert gas.
14. Method to any of the Claims 9 to 12 characterized in that the process is earned out in free atmosphere, i.e. in free air, at room temperature and normal atmospheric pressure.
15. Method to any of the Claims 9 to 14 characterized in that extraneous substances are incorporated into the geometrically defined areas by the melting process.
16. Method to any of the above-mentioned Claims characterized in that the depth, or thickness of the rank a of interaction, respectively, according to the objective of the processing action is adjusted by selection of the wavelength, or range of wavelength, respectively, and the power density of the electromagnetic radiation as well as the time of interaction between the electromagnetic waves and the geometrically defined areas.
17. Method to any of the above-mentioned Claims characterized in that the lateral extension of the range of interaction, the time of interaction and the intensity are realised by combination of the relative motion between the beam and the workpiece as well as by methods of dynamic beam forming and beam focussing.
18. Method to any of the Claims 9 to 17 characterized in that the energy input is carried out using a pulse-type laser.
19. Method to Claim 18 characterized in that the time of interaction between the laser beam and the geometrically defined areas is equivalent to the pulse length of the laser.
20. Application of the component to Claim 1 to 8 characterized in that said components having a melted area are joined with each other by the solidified wood melt free of pyrolytic degradation products.
21. Application of the component to Claim 20 characterized in that wood-free materials are joined with said component having a melted area, by the solidified wood melt free of pyrolytic degradation products.
22. Application of the component to Claim 21 characterized in that the wood-free materials are transparent polymers and/or fibrous materials.
23. Application of the component to Claim 20 to 23 characterized in that particles or pigments are incorporated into the solidified wood melt free of pyrolytic degradation products.
With 1 sheet of drawings.
With 1 sheet of drawings.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19745706.1 | 1997-10-16 | ||
| DE19745706A DE19745706B4 (en) | 1997-10-16 | 1997-10-16 | Method for producing a component from wood |
| PCT/DE1998/003034 WO1999020442A1 (en) | 1997-10-16 | 1998-10-16 | Wood component and a method for the production and application of the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2306630A1 true CA2306630A1 (en) | 1999-04-29 |
Family
ID=7845709
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002306630A Abandoned CA2306630A1 (en) | 1997-10-16 | 1998-10-16 | Wood component and a method for the production and application of the same |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP1021283A1 (en) |
| AU (1) | AU1554999A (en) |
| CA (1) | CA2306630A1 (en) |
| DE (1) | DE19745706B4 (en) |
| WO (1) | WO1999020442A1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8056236B2 (en) | 2005-02-23 | 2011-11-15 | Flooring Industries Limited, Sarl | Method for manufacturing floor panels, as well as floor panel obtained by means of such method |
| BE1016464A3 (en) * | 2005-02-23 | 2006-11-07 | Flooring Ind Ltd | Manufacture of laminate floor panels used in forming floating floor covering, involves forming floor panels at least partially using laser treatment of board-shaped material |
| EP2033752B8 (en) | 2007-09-05 | 2015-12-16 | Markus Brühwiler | Exterior finishing and method for its manufacture |
| FR2929876B1 (en) * | 2008-04-15 | 2014-04-25 | Faurecia Interieur Ind | PROCESS FOR TREATING A WOODEN ELEMENT OF A PARTICULAR SPECIES |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60127102A (en) * | 1983-12-13 | 1985-07-06 | 大建工業株式会社 | Ornamental material |
| AU6563986A (en) * | 1985-12-06 | 1987-06-11 | Hughes Technology Pty. Ltd. | Laser sawmill |
| DE4033255C2 (en) * | 1990-10-19 | 1994-02-24 | Daimler Benz Ag | Process for high-contrast highlighting of the early wood portion compared to the late wood portion in the grain pattern of a low-contrast wooden part in the original condition due to the effect of heat |
| RU1790487C (en) * | 1990-12-21 | 1993-01-23 | Иркутский научно-исследовательский институт лесной промышленности | Method for welding wood |
| FR2710290A1 (en) * | 1993-09-20 | 1995-03-31 | Prieur Sa | Glulam (adhesive-bonded laminate) profile and joinery (woodwork) products having plies made of wood rendered refractory |
| DE9402681U1 (en) * | 1994-02-18 | 1994-04-21 | Aesculap Ag | Device for processing glass, plastic, semiconductors, wood or ceramic using laser radiation |
| SE9400934L (en) * | 1994-03-21 | 1995-09-22 | Joachim W O Seltman | Method and apparatus for obtaining a wood surface with exposed cell structure |
| JPH09155814A (en) * | 1995-12-11 | 1997-06-17 | Tomiyasu Honda | Compressed wooden material and production thereof |
| FR2751579B1 (en) * | 1996-07-26 | 1998-10-16 | N O W New Option Wood | WOOD PROCESSING PROCESS WITH GLASS TRANSITION STAGE |
-
1997
- 1997-10-16 DE DE19745706A patent/DE19745706B4/en not_active Expired - Fee Related
-
1998
- 1998-10-16 WO PCT/DE1998/003034 patent/WO1999020442A1/en active Application Filing
- 1998-10-16 AU AU15549/99A patent/AU1554999A/en not_active Abandoned
- 1998-10-16 EP EP98959732A patent/EP1021283A1/en not_active Withdrawn
- 1998-10-16 CA CA002306630A patent/CA2306630A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| DE19745706A1 (en) | 1999-04-29 |
| AU1554999A (en) | 1999-05-10 |
| WO1999020442A1 (en) | 1999-04-29 |
| DE19745706B4 (en) | 2005-06-02 |
| EP1021283A1 (en) | 2000-07-26 |
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