Modifying a wood material utilizing formaldehyde polymer and sulfur dioxide
US5318802A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1993 |
| Grant date | Jun 7, 1994 |
| Priority date | — |
| Expiry date | Apr 20, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L61/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
In a method of treating a raw wood material with a formaldehyde polymer in the presence of sulfur dioxide at a reaction temperature within a reaction vessel to obtain a modified wood material, sulfur dioxide is supplied into the reaction vessel when a gas pressure of the formaldehyde polymer within the reaction vessel is 4.00.times.10.sup.4 Pa or more. In addition, a concentration of the formaldehyde polymer is in a range of 30 to 350 mol/m.sup.3 of formaldehyde monomer, and a molar ratio of the formaldehyde polymer to sulfur dioxide is in a range of 10 to 350. As the formaldehyde polymer, for example, trioxane, tetraoxane, or paraformaldehyde is used. The modified wood material manufactured by the method including the above conditions shows excellent dimensional stability while a discoloration thereof is effectively prevented. Therefore, the modified wood material is particularly fit to use for an interior furniture, musical instrument and a bath tub, etc.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.