The Treatability of Refractory Softwoods


  • John F. Siau
  • Jeffry S. Shaw


The relationship between the permeability and treatability of seven eastern coniferous species and five western species was investigated. A linear relationship was found between fractional volumetric retention and logarithm of [permeability (pressure/viscosity)0.32] for the eastern woods and logarithm of [permeability (pressure/viscosity)0.18] for the western woods, indicating that permeability is the most significant factor affecting retention. The difference in the results for the two groups was attributed to variations in gross anatomical structure. The pressure impregnation of specimens with a light hydrocarbon oil and Cellon solvents followed by their subsequent removal resulted in a slight decrease in air permeability. This was interpreted as an indication that no significant change in the sizes of the pit openings occurred because of treatment with these solvents.


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