Treatment of formaldehyde laden wood panels to reduce excess formaldehyde
US4376807A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 1980 |
| Grant date | Mar 15, 1983 |
| Priority date | — |
| Expiry date | Oct 27, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/3196
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A substantial reduction of free excess formaldehyde in formaldehyde laden wood panels is achieved by coating at least one side of the panel with a salt solution containing an ammonium cation such as a 10-15% aqueous solution of ammonium bicarbonate. After coating, a barrier is placed over the coated surface such as by stacking a plurality of similarly coated panels with the barrier being maintained sufficiently long to allow ammonia gas generated from normal degradation of the ammonium salt to migrate to the free formaldehyde zone where the ammonia gas reacts with the formaldehyde to produce a stable, low volatility reaction product. The treatment may be applied to raw or finished panels and the generated ammonia gas reacts in the stacked panels with formaldehyde in both the glue lines and the formaldehyde based finish topcoating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.