Chemical Treatment To Improve Wood Finishing


  • Younis H. Suleman
  • Sahar H. Rashid


black poplar (<i>Populus nigra</i>), finishing


Black poplar (Populus nigra L.) boards were treated with different chemicals including sodium hydroxide, aluminum chloride, and ammonium chloride in aqueous solution; finished with commercial grade varnish; and exposed outdoors for one year to study the stability of the finishing after treatment. The appearance of the boards before and after a one-year exposure was found to be related to the type of chemical used. In the case of NaOH solution, the increase of the treatment temperature from 21°C to 70°C improved the penetration of NaOH solution and subsequently the distribution of finish material in the wood. The absorption, penetration depth, and finishing of wood were markedly better with aqueous solutions of NaOH, compared to AlCl3, NH4Cl, and water. The pretreatment of boards with the different chemicals decreased the photochemical discoloration of finished boards to the lowest limit after they were exposed to natural sunlight for one year.


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