CA2211637C - A method of producing impregnated wooden products - Google Patents
A method of producing impregnated wooden products Download PDFInfo
- Publication number
- CA2211637C CA2211637C CA002211637A CA2211637A CA2211637C CA 2211637 C CA2211637 C CA 2211637C CA 002211637 A CA002211637 A CA 002211637A CA 2211637 A CA2211637 A CA 2211637A CA 2211637 C CA2211637 C CA 2211637C
- Authority
- CA
- Canada
- Prior art keywords
- article
- wooden
- impregnating agent
- agent
- impregnated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- 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
- B27M1/02—Working of wood not provided for in subclasses B27B - B27L, e.g. by stretching by compressing
-
- 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
- B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
- B27K3/02—Processes; Apparatus
- B27K3/0207—Pretreatment of wood before impregnation
-
- 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
- B27K5/007—Treating of wood not provided for in groups B27K1/00, B27K3/00 using pressure
-
- 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
- B27K2240/00—Purpose of the treatment
- B27K2240/30—Fireproofing
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Mechanical Engineering (AREA)
- Chemical And Physical Treatments For Wood And The Like (AREA)
Abstract
The present invention relates to a method of producing an impregnated wooden product from a wooden article. The article is pressed isostatically with a pressure exceeding 1,000 bars in a first method step. The wooden article is then placed in a bath containing a liquid-impregnating agent in a second method step and allowed to swell so that at least a part of the impregnating agent is absorbed by the article.
The method may optionally be supplemented with a third method step in which the article is pressed isostatically with a pressure exceeding 1,000 bars, so as to form a hard element. The third method step may alternatively be applied to a conventionally pressure-impregnated article.
The method may optionally be supplemented with a third method step in which the article is pressed isostatically with a pressure exceeding 1,000 bars, so as to form a hard element. The third method step may alternatively be applied to a conventionally pressure-impregnated article.
Description
- .- 1 A METHOD OF PRODUCING IMPREGNATED WOODEN PRODUCTS
The present invention relates to a method of producing impregnated wooden products from wooden articles.
Various impregnating methods are known for treating wooden articles with the intention of preventing the occurrence of wood mould and wood ro.t . Such methods may involve placing the articles in a chamber, evacuating the chamber, introducing an impregnating agent thereinto, and then re-pressurizing the chamber. The impregnating liquid enters the wood cells to a greater or a lesser extent.
It is also known to produce hard elements, for instance floor boarding, by compressing different types of wooden products in conventional presses . The pressures applied in this regard do not normally exceed 500 bars, even though much higher pressures have been proposed. The use of these much higher pressures has not found practical use in the present context however, due to the fact that in conventional presses these high pressures can only be achieved in the case of very limited surface areas.
.. Application of this latter method normally results in considerably deformation of the material during compression.
This deformation is ndt only caused in the direction in which the pressing forces act, but also transversely to this direction. This is because the material is pressed between an upper and a lower press plate which enables the wooden articles to expand freely in a lateral direction. When counter-pressure devices are used to impede this lateral expansion of the material, the presses become complicated and their use is limited to specific dimensions; see for instance Swedish Publication SE 601162 in this regard.
Patent abstract of Japan, vol. 16, No. 153, m-1235, abstract of JP-A-4-7101, discloses a method where wooden articles are ANcwCcD SI-~~~~T
compressed in a conventional pressing apparatus in a first step. The article is then immersed in a treating liquid in order to impregnate the article. Finally, the article is dried by treatment with heat.
Swedish Patent Application 9303821-4 describes a method of producing hard elements from a wooden article by applying very high pressures, i.e. pressures higher than 1,000 bars, and an isostatic pressing process, i.e. a process in which a uniform pressure is applied over the whole of the outer surface of the article. These high pressures can be applied to large surface areas by means of a so-called Quintuspress.
The present invention relates to a further development of the method described in the aforesaid Swedish and Japanese patent applications, and the object of the invention is to provide an impregnating method which will produce fire-retardant and/or rot-resistant and/or shape-durable elements and hard, impregnated elements respectively.
Accordingly, in one aspect of the invention, there is provided a method of producing an impregnated wooden product from a wooden article, comprising: a) pressing the wooden article to substantially compact the wood; b) immersing the compressed wooden article in a bath of liquid impregnating agent whereby the immersed article is permitted to swell so that at least a part of the impregnating agent is absorbed by the article; c) and pressing the wooden article a second time, characterized in that the wooden article is compressed by an isostatic pressure exceeding 1 000 bar in steps a) and c); and in that the impregnating agent is a fire-retardant agent, a rot-preventing agent or a glue.
In the method according to the present invention, a wooden article is pressed isostatically in a first step at a pressure in excess of 1,000 bars, either in a so-called Quintuspress* or by means of some other appropriate pressing method. In this regard, the extent to which the article is compressed will depend on its dry solids content, the fibre direction, its hardness and other properties. However, one of the cross-sectional dimensions of the article will normally be reduced by between 20-50% in the pressing operation, wherewith the wood cells are pressed together.
The wooden article is then relieved of load.
l0 The article is placed in a liquid bath containing impregnating agent in a second step, wherein the article successively *Trade-mark 2a . .. . 3 swells as a result of liquid penetrating into and being absorbed by the wood cells. The liquid penetrates into the cells so that the article is completely impregnated through-out. Expansion of the article is contingent on the material properties thereof and also on the time during which the article remains in the bath, among other things. Normally, ' a marked expansion takes place within the course of some hours, and the material returns to its original form within this time period in certain cases. Suitable impregnating agents are fire-retardant liquids, rot-retardant liquids,or glue. However, in order for the liquid to penetrate into the cells, it is necessary for the liquid to have a high wood penetration capacity.
Tests have been carried out with pine test pieces having a thickness of 24 mm, which was reduced to 12 mm by the isostatic pressing operation, whereby the density of the test pieces increased to immediately below 1 kg/dm3: When placed in a bath containing a fire-retardant agent, the test pieces expanded to their original size within the space of one hour.
The test pieces were then dried and divided into smaller parts and attempts were made to ignite parts which had been located centrally in the article and parts which had beer_ located on the sides thereof. It was, however, impossible to ignite any of these.parts, which indicated that the fire-retardant liquid had penetrated to the central parts of the article.
In the third step of the aforesaid method, the article is again compressed isostatically at a pressure exceeding 1,00G
bars, therewith obtaining a hard element which is fire-resistant, rot-resistant and also shape-durable when glue is used.
flMEidDED SI~FFT
The present invention relates to a method of producing impregnated wooden products from wooden articles.
Various impregnating methods are known for treating wooden articles with the intention of preventing the occurrence of wood mould and wood ro.t . Such methods may involve placing the articles in a chamber, evacuating the chamber, introducing an impregnating agent thereinto, and then re-pressurizing the chamber. The impregnating liquid enters the wood cells to a greater or a lesser extent.
It is also known to produce hard elements, for instance floor boarding, by compressing different types of wooden products in conventional presses . The pressures applied in this regard do not normally exceed 500 bars, even though much higher pressures have been proposed. The use of these much higher pressures has not found practical use in the present context however, due to the fact that in conventional presses these high pressures can only be achieved in the case of very limited surface areas.
.. Application of this latter method normally results in considerably deformation of the material during compression.
This deformation is ndt only caused in the direction in which the pressing forces act, but also transversely to this direction. This is because the material is pressed between an upper and a lower press plate which enables the wooden articles to expand freely in a lateral direction. When counter-pressure devices are used to impede this lateral expansion of the material, the presses become complicated and their use is limited to specific dimensions; see for instance Swedish Publication SE 601162 in this regard.
Patent abstract of Japan, vol. 16, No. 153, m-1235, abstract of JP-A-4-7101, discloses a method where wooden articles are ANcwCcD SI-~~~~T
compressed in a conventional pressing apparatus in a first step. The article is then immersed in a treating liquid in order to impregnate the article. Finally, the article is dried by treatment with heat.
Swedish Patent Application 9303821-4 describes a method of producing hard elements from a wooden article by applying very high pressures, i.e. pressures higher than 1,000 bars, and an isostatic pressing process, i.e. a process in which a uniform pressure is applied over the whole of the outer surface of the article. These high pressures can be applied to large surface areas by means of a so-called Quintuspress.
The present invention relates to a further development of the method described in the aforesaid Swedish and Japanese patent applications, and the object of the invention is to provide an impregnating method which will produce fire-retardant and/or rot-resistant and/or shape-durable elements and hard, impregnated elements respectively.
Accordingly, in one aspect of the invention, there is provided a method of producing an impregnated wooden product from a wooden article, comprising: a) pressing the wooden article to substantially compact the wood; b) immersing the compressed wooden article in a bath of liquid impregnating agent whereby the immersed article is permitted to swell so that at least a part of the impregnating agent is absorbed by the article; c) and pressing the wooden article a second time, characterized in that the wooden article is compressed by an isostatic pressure exceeding 1 000 bar in steps a) and c); and in that the impregnating agent is a fire-retardant agent, a rot-preventing agent or a glue.
In the method according to the present invention, a wooden article is pressed isostatically in a first step at a pressure in excess of 1,000 bars, either in a so-called Quintuspress* or by means of some other appropriate pressing method. In this regard, the extent to which the article is compressed will depend on its dry solids content, the fibre direction, its hardness and other properties. However, one of the cross-sectional dimensions of the article will normally be reduced by between 20-50% in the pressing operation, wherewith the wood cells are pressed together.
The wooden article is then relieved of load.
l0 The article is placed in a liquid bath containing impregnating agent in a second step, wherein the article successively *Trade-mark 2a . .. . 3 swells as a result of liquid penetrating into and being absorbed by the wood cells. The liquid penetrates into the cells so that the article is completely impregnated through-out. Expansion of the article is contingent on the material properties thereof and also on the time during which the article remains in the bath, among other things. Normally, ' a marked expansion takes place within the course of some hours, and the material returns to its original form within this time period in certain cases. Suitable impregnating agents are fire-retardant liquids, rot-retardant liquids,or glue. However, in order for the liquid to penetrate into the cells, it is necessary for the liquid to have a high wood penetration capacity.
Tests have been carried out with pine test pieces having a thickness of 24 mm, which was reduced to 12 mm by the isostatic pressing operation, whereby the density of the test pieces increased to immediately below 1 kg/dm3: When placed in a bath containing a fire-retardant agent, the test pieces expanded to their original size within the space of one hour.
The test pieces were then dried and divided into smaller parts and attempts were made to ignite parts which had been located centrally in the article and parts which had beer_ located on the sides thereof. It was, however, impossible to ignite any of these.parts, which indicated that the fire-retardant liquid had penetrated to the central parts of the article.
In the third step of the aforesaid method, the article is again compressed isostatically at a pressure exceeding 1,00G
bars, therewith obtaining a hard element which is fire-resistant, rot-resistant and also shape-durable when glue is used.
flMEidDED SI~FFT
Claims
1. A method of producing an impregnated wooden product from a wooden article, comprising a) pressing the wooden article to substantially compact the wood;
b) immersing the compressed wooden article in a bath of liquid impregnating agent whereby the immersed article is permitted to swell so that at least a part of the impregnating agent is absorbed by the article; and c) pressing the wooden article a second time, characterized in that the wooden article is compressed by an isostatic pressure exceeding 1 000 bar in steps a) and c);
and in that the impregnating agent is a fire-retardant agent, a rot-preventing agent or a glue.
b) immersing the compressed wooden article in a bath of liquid impregnating agent whereby the immersed article is permitted to swell so that at least a part of the impregnating agent is absorbed by the article; and c) pressing the wooden article a second time, characterized in that the wooden article is compressed by an isostatic pressure exceeding 1 000 bar in steps a) and c);
and in that the impregnating agent is a fire-retardant agent, a rot-preventing agent or a glue.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9500689-6 | 1995-02-24 | ||
SE9500689A SE510658C2 (en) | 1995-02-24 | 1995-02-24 | Ways to make impregnated wood products |
PCT/SE1996/000126 WO1996026054A1 (en) | 1995-02-24 | 1996-02-02 | A method of producing impregnated wooden products |
Publications (2)
Publication Number | Publication Date |
---|---|
CA2211637A1 CA2211637A1 (en) | 1996-08-29 |
CA2211637C true CA2211637C (en) | 2006-09-19 |
Family
ID=37056986
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002211637A Expired - Fee Related CA2211637C (en) | 1995-02-24 | 1996-02-02 | A method of producing impregnated wooden products |
Country Status (1)
Country | Link |
---|---|
CA (1) | CA2211637C (en) |
-
1996
- 1996-02-02 CA CA002211637A patent/CA2211637C/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
CA2211637A1 (en) | 1996-08-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6098679A (en) | Dimensionally stable oriented strand board (OSB) and method for making the same | |
US5685353A (en) | Method for compressive shape-drying of wood | |
EP0688260B1 (en) | Method for making hard-pressed wood | |
EP0809561B1 (en) | A method of producing impregnated wooden products | |
JP3675820B2 (en) | Method for producing a hard element of wood | |
US5204040A (en) | Method of making foam material | |
WO1995013908A9 (en) | Process for producing hard elements of wood | |
CA2211637C (en) | A method of producing impregnated wooden products | |
CA2248061A1 (en) | A method of pre-pressing fibre material in the manufacture of board products | |
JP3109775B2 (en) | Wood material heat treatment method | |
JP5629863B2 (en) | Heat-pressed wood and method for producing the same | |
CA2226139A1 (en) | Method for producing a hard wood element | |
JPH11151703A (en) | Manufacture of modified timber | |
US3130114A (en) | Process of manufacturing fibreboards and pressings from lignocellulose material | |
RU97115894A (en) | METHOD FOR PRODUCING SOAKED WOODEN ARTICLES | |
CA2343387A1 (en) | Composite article and method of making same | |
US709799A (en) | Method of impregnating wood. | |
JPH10296706A (en) | Decorative wood-based material and manufacture thereof | |
JP2002046107A (en) | Apparatus and method for forming wood | |
RU2098268C1 (en) | Method of production of packed modified wood and products from it | |
SE461796B (en) | IMPREGNATION OF LIGNOCELLULO MATERIAL IN THE FORM OF PIECE OF AT LEAST 100 MM LENGTH | |
SU1655780A1 (en) | Method of producing modified wood | |
NO753926L (en) | ||
JPS6046204A (en) | Manufacture of synthetic resin injected treated veneer |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
EEER | Examination request | ||
MKLA | Lapsed |